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Purveyors of Electronic, Musical and Vintage goods from then, now and in between. 
Since 1982.

VINTAGE STEREO RECEIVERS
RESTORED CLASSICS 


Vintage Stereo Receivers & Used Stereo Receivers that have been Refurbished. Brands / models of Classic / Vintage Stereo Receivers, 'Old-School' / 2-Channel stereo receivers, and Quadraphonic / Quad AM/FM receivers such as Kenwood KR, MCS, Pioneer SX / Pioneer SX-1980 for sale, Sansui G, Sony STR, Yamaha CR and Stereo / home audio receivers from the 1960's, 1970's & 1980's

.


 


 


CLASSIC 2-CHANNEL STEREO RECEIVERS . . .
 

    

     


         NEW LISTING 11/5/16

  (Click on above thumbnails to enlarge photos)
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE PIONEER STEREO RECEIVER
PIONEER SX-1980 RECEIVER
PIONEER'S FLAGSHIP
THE 'BIGGEST' 'BADDEST' RECEIVER TO EVER COME OUT OF THE PIONEER FACTORY
HUGE POWER AND SIZE!
340+ WATTS PER CHANNEL!!!
"NOT FOR THE 'FAINT OF POCKET-BOOK'
"
#...
0723
Circa 1978-79
MIJ

SOLD 3/27/17
SHIPPING TO MONTANA


ü Our technician has completely gone through and 'Certified' this unit. Everything was cleaned inside and out including all switches, controls and contacts. Extensive cleaning of unit internally.

ü Power Supply circuit board and both driver boards had all of their 'electrolytic capacitors' replaced (a note on this; prior to replacing the capacitors, we 'dialed the unit in perfectly' for DC offset, Bias and clean output sine waves to beyond rated power. After replacing all the Electrolytics on the power supply circuit board and the amplifier driver boards, the unit was again measured to perfect levels. The old capacitors ALL checked fine, so basically we have baggies of about 50, 35 year old capacitors that are in fine shape. Just FYI.)

      

     


ü Control potentiometers were 'flooded' w/ 'De-OxId' and are quiet (very difficult to do as 'tone' section must be painstakingly removed).

ü ALL Switches were flooded with cleaner with emphasis especially on the always at issue, switches / controls such as the 'Function' selector, 'Tape Monitors', '-20dB Muting', and 'Tone Bypass'.


ü  Internal fuses checked for correct value / function and replaced where necessary (and there were some 'in-correct' values we found).

ü  World AC Power correctly set for North American current.

ü This unit has a tuner based on the other Pioneer models, with a couple of additional circuits. The additional circuits are the 'Quartz Lock' and the 'Fine Tune', both of which are indicated by LED's near the 'Stereo' LED indicator. These two additional circuits are an issue with SX-1980's we've discovered, and escalating the unit to an outside tech firm, did not improve their function. While the unit's tuner sounds great, it will drift after being left on for a few hours. Could be 2 or could be 24, but it will drift and need a slight 'nudge' on the tuning knob to bring it back into station center. Also, the 'Fine Tune' light is on when the station is slightly 'off center', and not when it's perfectly tuned. Both our senior techs and two outside repair shops, 'senior techs' spent 8-10 hours on these two aspects, with no appreciable improvement. The 4th tech discovered that the unit could be put into a mode which defeated the additional circuits (which when left intact caused a very faint, cyclical noise), so now it functions like the tuner on the Pioneer SX-1280, 1080, 980. Sonically the tuner sounds great, pulls in stations fine, has great side band rejection, and great 'Stereo' sound. Only issue is the above mentioned 'drift' after a few straight hours of running.

ü  We of course aligned the tuner front-end on both AM & FM bands for optimum performance as older tuner components will have 'drifted' over the years.

ü  Amplifier section had output bias and DC offset adjusted to spec levels

ü  We bought ALL the remaining AEL-029 dial bulbs from Pioneer a few years ago. These are the original, official 'Stanley 8V' with blue tinting. We purchased a couple dozen and are probably worth their weight in gold. We have not used them on any of our Pioneer restoration, and have been using a fine substitution. We were saving them for a Pioneer SX-1980 to come along. Well, this unit got them. All four dial lamps and meter lamps replaced with ORIGINAL PIONEER AEL-029's. The balance of the light bulbs, including ALL indicator lamps, the dial pointer lamp, Speaker indictors, 'Stereo' indicator, input / function indicators were replaced with new.

ü All 4 power supply filter capacitors independently tested.

ü All inputs tested and both sides produce clean and even sine waves into 'brick-wall' 8 & 4 ohm loads!

VERY GOOD FM TUNER!
FM reception as well great and IMPECCABLY CLEAN!!! All inputs tested and both sides produce clean and even sine waves into 'brick-wall' 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions test fine. Following restoration procedures, the unit was ran continuously at medium volume, as all our amplifier / receivers are, into a load with "Loudness" on and both Tone Controls at 10 for 48 hours into a 4 Ohm load. Cosmetically, the top, horizontal edge of the face plate has some light / shallow striations running it's length, there's a scuff on the volume knob, and at some point in it's past, the Walnut, wood 'half bonnet' was re-veneered in a lighter shade of walnut (see photos above). Again, overall this is a fabulous receiver. You won't be disappointed. Total restoration time investment between two senior techs ~38 hours.  

On our test bench, the internal amplifiers of this receiver #...0723 produced 45 volts per channel @ 8 ohms with 1Khz input for 253 watts and 37.4 volts per channel @ 4 ohms with 1Khz input for 349 watts via discrete outputs with 1 kHz input.
 AC Idle current @ .7A,
DC balance adjusted to 0 ±3mVDC and DC offset output adjusted to <~30mVDC either channel. Floor noise measured 0mVAC / >60dB either channel.
   ____________________________


The Pioneer SX-1980 Stereo Receiver. This is the first one of these we've had in 19 years. Even as a Pioneer dealer, back in the day, the stores I worked at didn't carry this model as it was generally TOO EXPENSIVE for the market (equaling about 10% of the average persons yearly take-home pay).
Classic looking brushed-aluminum silver face and encased in a real wood Walnut veneer cabinet with solid Walnut wood corner caps. This is the most SERIOUS receiver Pioneer ever marketed and as listed above, this one has been 'certified' following the refurb by Oak Tree Vintage and is in incredible condition!!! 
An interesting note on this one is that the consignor picked it up from a member of the Denver based, 1970's band, 'Sugar Loaf'
(famous for hit's such as "Green Eyed Lady" and "Don't Call Us, We'll Call You"). It was speculated to have been the amp in their practice space.

Pioneer SX-1980 Features:
 

Tuner features:
- Weighted flywheel analog "slide-rule" tuning
- FM Muting Selector (separate from the 'Stereo' selector)
- Dual analog 'Signal Strength' and 'Tuning' VU meters
- FM Multi-Path Detector (handy when installing antenna for best positioning)
- Dual position FM De-emphasis selectable for 25 or 75 msec 

Pre-Amp / 'Control Amplifier' / Power Amp features:
- Direct Coupled (DC) Power Amp architecture
- A or B or C, or A+B or A+C, or Off speaker selector
- Defeat-able 4-control / 2-band EQ. (Bass controls centered at 50 or 100 Hz and Treble @ 10k or 20kHz)
- Super quality de-tented Tone and Volume controls
- "Loudness" function to boost Bass and Treble in relationship to Mid frequencies at lower volume levels for a much fuller sound.
- Stereo / Mono selector (for entire pre-amp section, not just FM tuner)
- Hi filter for reducing tape hiss / electronic hiss & noise and record static
- Built-in 'Low' Filter to eliminate excess rumble from sources such as turntables
- Pre-Amp Out / Power-Amp Input / Loop
- Dual analog 'Power' VU meters
- -20dB Audio Muting for instant lowering of volume without adjusting the volume control. Great for ringing phones and cuing a record on your turntable

Inputs:
- Dual Phono / turntable inputs with Built-In Phono Pre-Amp
- Dual tape monitors with standard RCA I/O's (Tape Monitors can be used with Tape / Video / CD / DVD / VCR / DAT / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS® CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc)
 - Tape 'Dubbing' capability for Tape 1 to Tape 2
- Aux input (may also be used for Video / CD / DVD /DAT / VCR / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS®  etc.)
- Microphone input (be very careful with your 'home audio' speakers when inserting a mic into any stereo receiver)
- 1/4", stereo headphone jack
- Dual Phono inputs with phono 2 doubling as the Microphone input
- 4- Position phono cartridge loading selector with settings at 100, 200, 300 or 400pf for fine tuning phono pre-amp
- 3- Position cartridge impedance selector with settings at 10k, 50k, or 100k for fine tuning phono pre-amp
to your cartridge (a must for serious vinyl players)
- 1/4" front mounted Microphone input
- -20db Audio Muting

Other:
 - Pre-out / Main-in loop
 - 3 AC outlets (1 switched / 2 un-switched) for a total capacity of 300 watts


Original Pioneer SX-1980 Specifications:


  "The Pioneer SX-1080 has a continuous power output of 270 Watts per channel min @ 8 ohms, from 20 hertz to 20,000 hertz with no more than 0.03% THD (measured utilizing AUX input)"
 
POWER / PRE AMP:

THD:
0.02% @ 135 WPC @ 8 Ohms & 0.03% @ Full Rated Output @ 8 Ohms
Freq Response of power amp section:
@ full rated power 20-20kHz. @1W it's rated down to 0.006%
Potential frequency response of power amp section @ 1w:
5 Hz to 100 KHz, +0 dB, -3 dB
IMD utilizing AUX: 0.03% @ 270 WPC 20-20kHz
0.02% @ 135 WPC 20-20kHz
0.006% @ 1 WPC 20-20kHz

Hum / Noise (S/N) Ratio: 120dB (10 db greater than the Pioneer SX-1080)
Damping factor:
40 @ 8Ω full bandwidth
Power Amp Input Impedance:
50k Ohms
Power Amp Input Sensitivity for Full Output:
2V (coupled with the 2V output of the pre-amp, has a lot to do with the VERY high S/N listed above)
Tone Control ranges:

Sub Bass: +/-5dB @ 50Hz
Bass:
+/-10dB @ 100Hz
Treble: +/-10dB @ 10kHz
Upper Treble: +/-5dB @ 20kHz
Hi Filter: 6
KHz, 12dB/octave
(most are 6dB/ octave)
Lo / 'Sub' Filter: 15Hz, 12dB/octave (most are 6dB/ octave)
Loudness Contour: + 6dB at 100 Hz, + 3dB at 10KHz at -40dB on volume control
Pre-Amp Input Impedance: 50k Ohms
Pre-Amp Input Sensitivity at all inputs except phono & mic: 150mV
Microphone Input  Sensitivity / Impedance: 7.5mV / 50k Ohms
Input Freq Response (except Phono & Mic): 5-80kHz
Tape Output Impedance: 50kΩ
Tape Output:
150mV

Pre-Amp Output
Level & Impedance: 2V / 1k Ohms (coupled with the 2V input of the power-amp, has a lot to do with the VERY high S/N listed above and double the SX-1080)
Pre-Amp THD @ rated output: <0.01%

TUNER SPECS FOR FM:
Freq Response:
The full 30-15kHz per FCC Regulations
S/N:
 > 85 dB Mono @ 65dBf
S/N: 
> 75 dB Stereo @ 75dBf
Useable Mono RF Sensitivity dBf / μV:
8.7dBf / 1.5μV
Capture Ratio:
1.0dB
Signal for 50dB quieting, Mono dBf / μV:  
11.5dBf / 2.2μV
Signal for 50dB quieting, Stereo dBf / μV:  36dBf / 34μV
De-Emphasis: selectable 25 or 75 μ-sec
THD w/ 100% modulation @ 100Hz, Mono: 
0.05%
THD w/ 100% modulation @ 1kHz, Stereo: 
0.07%
THD w/ 100% modulation @ 6kHz, Mono:  0.02%
IF Response Ratio: 
120dB
(20db greater than the Pioneer SX-1080)
Stereo Sub-Carrier Rejection: 
65dB

AM Carrier Rejection:
60dB
(5db greater than the Pioneer SX-1080)
Spurious Rejection:
120 dB
(30db greater than the Pioneer SX-1080)
Image Response Ratio:
120 dB
(30db greater than the Pioneer SX-1080)
FM Alternate Channel Selectivity: 
80dB
Muting Threshold dBf / μV:
19.2dBf / 5μV
Stereo Separation:
50dB @ 1kHz or 40dB @ 30-15kHz

TUNER SPECS FOR AM:

RF Sensitivity: 300uV/meter or 15uV @ binding posts
Alternate Channel Selectivity:
26dB
IF Response Rejection Ratio:
70dB
(30db greater than the Pioneer SX-1080)
Image Response Rejection Ratio:
70dB
(30db greater than the Pioneer SX-1080)
Signal to Noise Ratio:
55dB
(5db greater than the Pioneer SX-1080)

PHONO SECTION SPECS:
Freq Response:
20-20kHz ±0.2dB
S/N:
87dB, ref 'shorted' input (11dB greater than the PIoneer SX-1080!!!)
Input Sensitivity:
2.5 mV with load selectable 10k, 50k or 100kΩ
Overload limit:
300 mV @ 1kHz w/ THD of 0.03%
Cartridge Load Capacitance: 100,200,300,400pF


Huge power supply in the Pioneer SX-1980 featuring Dual independent, toroidal transformers (in one housing) for a 'TRUE DUAL POWER SUPPLY', followed by 4X 100V / 22,000μF power supply filter caps to feed the huge output transistors.
Again, we have completely gone through the Pioneer SX-1980 Stereo Receiver, as stated above and 'certified' it's ready to go!
The only 'performance' issues would be the previously mentioned tuner LED's in FM mode, and cosmetically, the scuffs on the top, horizontal face edge, the volume knob scuff and the lighter, real wood Walnut cabinet.  Unit looks great and sounds HUGE! This is truly one of the "BIGGEST BOYS" when it comes to CLASSIC STEREO RECEIVERS! Includes a pdf, 'e' copy, download of the Pioneer SX-1980 owners / users / instruction manual, Service manual and original brochure if the purchaser so desires. Measures 22.25" wide x 20" deep x 8.25" high and weighs a HEAVY 73 lbs unpacked. Includes our 90 day limited warranty!
PIONEER SX-1980 STEREO RECEIVER
 Cond. 8.5
SOLD 3/27/17
SHIPPING TO MONTANA

(C) M.R.

links to a couple of "Shoot Out" articles featuring the SX-1980;


https://www.cnet.com/news/how-can-30-year-old-receivers-sound-better-than-new-ones/

http://www.iavscanada.com/receiver-shoot-out-vintage-vs-high-tech/

(Due to the dimensions and / or weight of this receiver, Packing / Shipping will be somewhat more 'involved' than typical. A custom built box may be necessary to order. While we order custom built boxes often, this can sometimes delay shipping by 5-10 days)

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)
 

 

 

 

 

    

NEW LISTING
12/30/16
(Click on above thumbnails to enlarge photos)

CheckMarkSmall_web.jpg (792 bytes) warranty

VINTAGE PIONEER STEREO RECEIVER
PIONEER SX-V90 RECEIVER
HUGE POWER AND SIZE!

217 WATTS / CHANNEL!*
#...0
23S
Circa 1984-85
MIJ

SOLD 4/19/17
SHIPPING TO CALIFORNIA

VERY impressive looking and performing digital "Power-House" receiver. Features "Non-Switching" Amplifier for quieter performance. Handsome mixture of the classic silver face look with digital tuner performance. Readout looks like a Corvette dashboard when fired up.

Our technician has completely gone through and 'Certified' this unit. Unit disassembled, then everything was cleaned inside and out including all switches, controls and contacts. Extensive cleaning of unit internally. Controls were 'flooded' w/ 'De-OxId' and are quiet. Internal fuses checked for correct value / function and replaced where necessary. We also checked the tuner front-end on both AM & FM bands for optimum performance as older tuner components may have 'drifted' over the years. Amplifier section had output bias and DC offset adjusted to spec levels. All indicators checked and are LED's for trouble-free service.
All inputs tested and both sides produce clean and even sine waves into 'brick-wall' 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions test fine, including tuner pre-sets. Following restoration procedures, the unit was ran continuously at medium volume, as all our amplifier / receivers are, into a load with "Loudness" on and both Tone Controls at 10 for 48+ hours. You will not be disappointed.


While this model was originally rated at 125 watts / channel, on our test bench, this unit's (#...023S) amplifiers produced 32 volts per channel at 8 ohms for 128 watts per channel or 29.5 volts at 4* ohms for 217 watts per channel. Floor noise measured at 0mVAC. 
 AC Idle current at 900mA. DC offset adjusted to <13mV L or R. Bias adjusted

Pioneer SX-V90 Features include:


-  Digital Quartz synthesized  tuning with 10 presets for both AM & FM
-  Auto / Manual tuning modes
- Digital signal strength indicator
- FM tuner steps selectable between 50kHz or 100 kHz
- AM tuner steps selectable between 9kHz or 10kHz
- FM De-Emphasis selectable between 50 msec or 75 msec
- Non-switching Amplifier transistors
- Built-in Subsonic filter for reducing turntable rumble
- Stereo / Mono mode selector
- Loudness switch
- Separate Bass and Treble
- Electronic volume control
- Dual Phono / turntable input
- Dual tape monitors with standard RCA I/O's (Tape Monitors can be used with Tape / Video / CD / DVD / VCR / DAT / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS® CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc)
- Tape 'Dubbing' capability for Tape 1 to Tape 2
- CD input (may also be used for Video / CD / DVD /DAT / VCR / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS®  etc.)

- 3 Video Inputs
(may also be used for Video / CD / DVD /DAT / VCR / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS®  etc.)
- Video 1 to 2 copy

- Moving Coil / Moving Magnet phono cartridge selector
- 20 dB Audio Muting
- 2 quick access volume presets
- Simulated Stereo for video inputs

- Front and Rear Video outputs
- Pre-amp out / Power amp in loop
- Built-in AM ferrite stick antenna on swivel mount
- Dual AC outlets (1 switched / 1 un-switched)
-True WORLD AC POWER  allows unit to be operated on 50 or 60 Hz AC and will select voltages from 110v, 120v, 220v and 240 volts AC input. 


Original Pioneer SX-V90 Specifications:

"The SX-V90 has a continuous power output of 125 watts per channel min. @ 8 ohms from 20 hertz to 20,000 hertz with no more than 0.005% THD (measured utilizing AUX input)"
 
POWER / PRE AMP SPECIFICATIONS:
THD: 0.005% @ full rated power
Freq Response of power amp section: @ full rated power 20-20kHz
Potential frequency response of power amp section @ 1w: 5 Hz to 100 KHz, + 0 dB, - 1,5 dB
 
IMD utilizing AUX: 0.005% @ full rated power / 20-20kHz
Hum / Noise Ratio: 100dB
Freq Response of PRE-amp section (non-phono input): @ full rated power 5-100kHz
Input Impedance:
50k Ohms
Input Sensitivity for Full Output:
1V

Tone Control ranges:

Bass:
+/-8dB @ 100Hz
Treble: +/-8dB @ 10kHz
z

Lo Filter: 20 Hz, 6 dB/octave
Loudness Contour w/ vol @ -40dB: + 6 dB at 100 Hz, + 3 dB at 10 KHz
Pre-Amp Output: 1V / 50k Ohms

TUNER SPECS FOR FM:

Tuning Range:
87.5MHz-108MHz
Freq Response:
20-15kHz (limited per FCC regs)
S/N: 
> 82 dB Stereo @ 80dBf
S/N:
 > 88 dB Mono @ 80dBf
Useable Mono RF Sensitivity in dBf:
10.8 dBf
Useable Mono RF Sensitivity in μV:
.95 μV
Capture Ratio:
1.0dB
THD w/ 100% modulation @ 1kHz, Mono: 
0.02%
THD w/ 100% modulation @ 1kHz, Stereo: 
0.04%
Spurious Rejection: 29.3 dBf (8μV)
Auto Tuning Level required: 100 dB
FM Alternate Channel Selectivity: 
85dB @ 40kHz (narrow)
Stereo Separation @ 1kHz: 
60dB (wide)

TUNER SPECS FOR AM:

RF Sensitivity:
220 uV/meter or 10 uV @ binding posts
Alternate Channel Selectivity: 60 dB
Signal to Noise Ratio: 50 dB

PHONO SECTION SPECS:
Freq Response:
20-20kHz
S/N MM:
86 dB
S/N MC:
67 dB
Input Sensitivity MM:
2.5 mV @ 50kΩ
Input Sensitivity MC:
0.25 mV @ 100kΩ
Overload limit MM:
150 mV
Overload limit MC: 14 mV


This receiver is in great functioning and cosmetic condition. As well as being 'HUGE' output power, it's 'specs' are impressive from both tuners, thru the pre-amp, on out to the amp outputs (check the specs above against other units). We have completely gone through this unit cleaning all contacts, controls, switches and pots. All functions test perfectly. 

This is one of the "BIG BOYS" when it comes to STEREO RECEIVERS! Includes a pdf, 'e' copy, download of the Pioneer SX-V90 owners / users / instruction manual. Measures 16.5" wide x 17.25" deep x 6" high and weighs 33 lbs unpacked. Includes our 90 day limited warranty!
PIONEER SX-V90 STEREO RECEIVER
Cond. 8.5++

SOLD 4/19/17
SHIPPING TO CALIFORNIA

 

 
(Above text, in it's entirety, property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

UPDATED LIST 2/1/17
Receivers Coming Soon
(or at least as time allows):

Kenwood KR-77
NAD 7120
(photos just finished!)
Sansui 5000A
Sansui QR-4500
Sansui QRX-6500
Sansui QRX-7500
Yamaha CR-2040
Yamaha RX-700U
and more...

 

 

 

 

Did you know?
While the company 'Pioneer' was officially established in 1961, the founder was actually developing speakers as early as 1937. In 1962 Pioneer marketed the worlds first 'separate component' stereo system for the home, and in 1975, the worlds first 'component system' for the car. In 1984 they introduced the first CD player for the automotive use (and I was selling it then). Pioneer had many other 'firsts' and continue to be a major 'player' in consumer, professional and industrial electronics.

 

 

 

    

        NEW LISTING
9/21/16

 
(Click on above thumbnails to enlarge photos)
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE STEREO RECEIVER
PIONEER SX-1500T STEREO RECEIVER 
#...6766
CIRCA 1968-70

MIJ!

for sale

We have completely gone through this cleaning inside and out including all contacts, switches and controls. All indicator lamps and dial / meter lamps replaced with new units, for trouble-free service. We also aligned the tuner for optimum performance on both AM and FM. All functions tested for perfect operation. All inputs tested and both sides produce clean and even sine waves! No power supply hum of any kind. It's dead silent! All functions tested for perfect operation.

Very impressive early Pioneer unit from their 1st series of "Solid State" Stereo Receivers. This was one of the most likely Pioneer receiver to come back with Vietnam GI's. First one of these we've had in 19 years to make it 'all the way through' our refurb / restoration, and was a 'good enough' likely candidate to begin with. Loaded with very useable features and looks great! The tuner on this one is VERY strong on both AM an FM, with AM reception that we would describe as 'AMAZING' (yes, I know, most folks couldn't give a hoot about AM, but a few of us here, including me do, and were very impressed by it's AM performance).

On our test bench, the internal amplifiers of this Pioneer SX-1500T receiver #...6766 produced 19.5+ volts per channel @ 8 ohms with 1Khz input for 47+ watts and 15+ volts per channel @ 4 ohms with 1Khz input for 57+ watts via discrete, TO3, metal cased output devices (4x Toshiba 2SC793 output transistors).
 AC Idle current at .2A. DC offset output <11mVDC either channel. Floor noise tested a 1.0mVAC.

   ____________________________

Pioneer SX-1500T Features include:

- Weighted flywheel analog slide rule tuning
- Separate L/R- Front/Rear Bass and Treble Controls
- Built-in Hi and Sub filters for reducing 19kHz pilot tone and 38kHz Harmonic in FM broadcasts, Tape Hiss and the Sub filter for reducing turntable rumble 
 - FM muting, separate from FM stereo selector
- Selectable FM Modes for Stereo or Mono
- AFC (Automatic Frequency Control) for improved FM reception
- Stereo Mode selector for entire Pre-Amp section selects; Mono, Right channel or Left channel input only & for Standard Stereo
- Analog lit VU meter for tuning/ signal strength
-  AUX Input (may also be used for Video / CD / DVD / VCR / iPod / DAT / MP3 / XM / SIRIUS etc.)

- Tape Monitor (Tape Monitors can be used with Video / CD / DVD / VCR / DAT / iPod / MP3 / XM / SIRIUS CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc) Dubbing can be used with CDR (CD recorders) units)
- Additional Direct Tape Head input (for older Reel Decks that did not have a built-in pre-amp)
- Selectable Tape Speed EQ input for either 7.5 ips or 3.75 ips. (used for older Reel Decks that did not have speed compensating EQ or Pre-Amps built-in)
- Dual Phono inputs with input 1 being selectable for either standard magnetic or can also be used with older Ceramic cartridge turntables. Input 2 is strictly for modern / standard magnetic cartridges
- Built-in AM ferrite antenna
- Speaker On / Off selector
- Rear mounted, Separation control for fine tuning FM MPX
- 2 convenience AC outlets with 1 being switched
- True “
WORLD AC POWER"
as it will work on both 50 or 60 Hz AC and voltages from 110-240 volts AC.

Original Pioneer SX-1500T Specs:
  
"The Pioneer SX-1500T has a RMS power output of 55 watts per channel min. @ 8 ohms from 20 hertz to 70,000 hertz with no more than 0.500% THD (measured utilizing AUX input), with a "Music Power Output" of 140Wpc @ 8 Ohms and 170Wpc @ 4 Ohms"
 
POWER / PRE AMP SPECIFICATIONS:

THD:
0.500% @ full rated power
Freq Response of power amp section: @ full rated power 20-70kHz
Power Bandwidth w/ all channels driven: 15-70,000Hz ±0dB
Damping factor:
25 @ 8Ω / 1kHz
Input Sensitivity / Impedance for AUX: 100mV / 100k Ohms @ 1kHz
Input Sensitivity / Impedance for Tape Monitor: 200mV / 100k Ohms @ 1kHz
Input Sensitivity / Impedance for Tape 'HEAD': 1.5mV / 120k Ohms @ 1kHz

TUNER SPECS FOR FM:
Freq Response:
30-15kHz (limited by FCC regulations)
FM TUNING RANGE: 87-108MHz
S/N: 
>65db Stereo
Useable Mono RF Sensitivity:
1.7 μV
Capture Ratio:
1dB
Image Rejection: 76dB @ 98MHz
Stereo Channel Separation @ 1kHz: 
37dB

TUNER SPECS FOR AM:
AM TUNING RANGE: 525-1605kHz
IHF Sensitivity:
20 μV
Image Rejection: 60dB @ 1MHz

PHONO SECTION SPECS:
Freq Response:
20-20kHz
S/N:
80 dB
Input Sensitivity 'MAGNETIC':
2.4 mV @ 50kΩ & @ 1kHz
Input Sensitivity 'CERAMIC':
51mV @ 90kΩ & @ 1kHz


Again, receiver has had complete service as stated earlier, and all functions tested. One note about this unit, as well as some of the 'Vietnam' era units is that the RCA I/O's on the rear panel are located fairly close together, and you'll need to utilize fairly 'normal' jacketed RCA connectors / plugs, and not some of the 'modern / FAT' jacketed versions as there's not enough clearance for them. Unit looks near NEW and sounds great. Face and all original knobs intact and look great as does the wood grain, case! Includes a pdf, 'e' copy, download of the Pioneer SX-1500T owners / users / instruction manual. Also comes with a pair of those, "worth their weight in gold" Pioneer speaker plugs. Measures 16.5" wide x 13.75" deep x 5.5" tall and weighs 25 lbs unpacked. Comes with our standard 90 day limited warranty.
PIONEER SX-1500T
Cond. 8.5+

$499.
(C) R.R.

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)
 

 

 
 










Did you know?
A SUPER LOW DISTORTION RATING COULD LIKELY BE A BAD THING!...
THD
(Total Harmonic Distortion) – THD is a measure of the how much a given audio device may distort a signal through the inevitable introduction of added harmonics or overtones. These figures are usually given as percentages. THD figures below approximately 1% are inaudible to most people (although market promotion efficiencies have 'brain-washed' much of the 'audio-public' into weighting low THD with almost 'holy grail' importance. I remember some manufacturers touting numbers as low as <0.003% in the early Eighties).  Low THD is not always an indication of a high quality amplifier. In fact, it is / was more commonly just the opposite. Some of the 'highest end' (read REALLY expensive) and certainly best sounding units will have distortions somewhere between .1% & 1%.
Low THD is only a simple 'bi-product' of 2 aspects. The first was an inordinate and increasing amount of 'global / negative feedback' built into amplifiers primarily to suppress distortion. This practice started to occur in the late 1970's and certainly was in 'full force' past the early 1980's for most 'main stream' consumer-grade audio amplifiers. Unfortunately this also 'suppressed' tone and 'punch' (musicality) but it made the numbers look good to the 'spoon fed' consumer (kind of like overly high speaker wattage numbers, and sorry if you're in that group and, most folks were so you're not alone). Secondly manufacturers were moving away from 'discrete-transistor' output designs to more 'monolithic' 'power-pack' output designs. While these designs reduced power supply requirements, thus reducing parts costs and weight (also translates to lower prices due to savings on freight from Asia) they generally sounded anywhere from somewhat 'anemic' compared with the designs from a few years previous, to completely 'gutless' and 'un-musical'. But, hey,… they had very low distortion figures….Can anyone say 'threw the baby out with the bath water'?

Excerpts of the above text from the website of one of the best Car Audio sites and stores in the world, 'Car-Fi' www.car-fi.com .

  

 
 

 

       



NEW ADDITION 2/1/17
   (Click on above thumbnails to enlarge photos)
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE
YAMAHA STEREO RECEIVER
YAMAHA R-8 / R8
BIG POWER
W/ WIRELESS REMOTE CONTROL

 Circa '81-'83
MIJ!
  for sale

  
We have completely gone through this unit cleaning everything including all switches, controls and contacts. We also aligned the tuner front-end for optimum AM & FM performance as older internal tuner components have always drifted on vintage gear over the years. Power indicator lamps replaced. New / Fresh tuner memory capacitor installed so that station memories function properly. Loudness control re-aligned for proper function. Entire display / readout works perfectly. All inputs and functions tested, and both amplifiers produces clean and even sine waves into static 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions test fine. Following restoration procedures, the unit was ran continuously at medium volume, as all our amplifier / receivers are, into a load with "Loudness" on and both Tone Controls at 10 for 72 hours.
  ____________________________
 
Great Yamaha R-8 receiver BIG power, Yamaha's "Natural Sound" with the convenience of a digital tuner. Very nice looking unit. The Yamaha R-8 was an upper level receiver with specs to prove it.
Yamaha R-8 Features include:
 
- Yamaha's "Natural Sound Stereo Receiver"
- Low Impedance Drive capabilities
- High Dynamic Power Output capability
- Digital tuning w/ Fine Tuning' feature
- 16 Random AM & FM tuner presets
- A, B and A+B speaker selector
- Separate Bass, Mid and Treble with high quality de-tented controls
- Record Out selector with bi-directional tape dubbing controls. (Separate "Record Out" allows recording from one source while you listen to another)
- Dual tape deck monitors (Tape Monitors can be used with Video / CD / DVD / VCR / DAT / iPod / MP3 / XM / SIRUS CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc)
- Dual A/V Inputs (A/V inputs can be used with Video / CD / DVD / VCR / DAT / iPod / MP3 / XM / SIRUS CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc)
- Accessory Loop / I/O used for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc. (the alternative to a 'true tape monitor')
- Phono / Turntable input with selector for either MM (Moving Magnet cartridge) or MC (Moving Coil Cartridge) (this feature alone could be worth hundreds of $$ if you are going to utilize a Moving Coil cart) (see specs below)
- CD Input (may also be used for Video / CD / DVD / VCR / DAT / MP3 / XM / SIRUS etc.)
- Yamaha's exclusive Variable "Loudness" control
- Auto DX / Local mode
- Auto / Stereo / Manual / Mono FM tuner modes
- "DNC" (Dynamic Noise Canceller) for externally input devices, such as Tape Decks / VCR's etc.
- Simulated Stereo (for simulating stereo on 'Mono' inputs such as older Video units
- Digital indicators for Station frequency, DX / Local mode, Stereo and Station Lock as well as an LED signal strength meter
- Wireless control capabilities (with optional and AND included Yamaha RS-9, wireless remote control)
- Dual AC convenience outlets located on the rear panel (1 switched @ 100 watts and 1 un-switched @ 200 watts for a total capacity of 300 watts) 

  
 
Original Specs:
"The Yamaha R-8 has a continuous / RMS power output of 85 watts per channel min. @ 8 ohms from 20 hertz to 20,000 hertz with no more than 0.015% THD (measured utilizing AUX input)"
 
POWER / PRE AMP SPECIFICATIONS:
Continuous Output Power per Channel; 85 Watts @ 8Ω & 0.015% THD w/ 20-20kHz input
100 Watts
@ 6
Ω & 0.03% THD w/ 20-20kHz input

Freq Response / Bandwidth of power amp section; @ 42.5 Watts
/ 8Ω  10-50kHz
Damping factor; 60 @ 8
Ω w/ 1kHz input
Signal / Noise ratio;  103dB @ CD / Tape (inputs shorted)
92dB @ Phono MM
w/ 5mV (inputs shorted)
75dB @ Phono MC w/ 500μV (inputs shorted)
Input Sensitivity AUX / Tape; 150mV / 47k
Ω
Tape Output level;
 150mv / 470
Ω
Channel Separation CD/Tape/Video; 60dB (inputs shorted)
Channel Separation Phono; 60dB (inputs shorted)
Bass Control Characteristics; ±10dB @ 50Hz w/ Turnover @ 350Hz
Mid Control Characteristics; ±12dB @ 1kHz w/ Turnover @ 1kHz
Treble Control Characteristics; ±10dB @ 20
kHz w/ Turnover @ 3.50kHz
Continuous "Loudness" Contour; Level-Related Equalization Attenuation to -40dB
Headphone Output / Impedance @ 0.015% THD; 0.75V /
270Ω
 

TUNER SPECS FOR FM;
Tuning Range;
87.5 to 108.0Mhz
Freq Response;
30-13kHz ±0.5 dB (limited by FCC regs)
S/N; > 81db Stereo
S/N; > 85db Mono
50 dB Quieting Sensitivity:
Mono (DX) 1.5μV (14.8 dBf)
Stereo (DX) 20μV (37.3 dBf)
Useable Mono Sensitivity (98 MHz, 30 dB Quieting); 0.75μV (75 ohms) 8.8dBf
Capture Ratio; 2.5dB DX, 1.2dB Loc
FM Alternate Channel Selectivity; 85dB
Spurious Response Ratio; 70dB
Image Response Ratio; 40dB
IF Response Ratio; 90dB
AM Suppression Ratio; 55dB
FM separation;  50dB @ 1kHz
 
TUNER SPECS FOR AM;
Tuning Range;
510 to 1620kHz
S/N; >50db
Useable Sensitivity; 250μV / m with loop antenna
S/N; > 50dB
Selectivity; 24dB
THD; 0.3% @ 400Hz
Spurious Response Ratio; 50dB
Image Response Ratio; 40dB
 
PHONO SECTION SPECS;
Freq Response MM;
20-20kHz
Freq Response MC; 30-20kHz

S/N;
92dB with MM cart and 5mV input
Input Sensitivity / Impedance w/ MM Cart;
160μV / 220Ω
Input Sensitivity / Impedance w/ MC Cart; 2.5mV / 47kΩ

RIAA Deviation MM; 20-20kHz with MM cart.±0.3dB
RIAA Deviation MC;
30-20kHz with MM cart.±0.5dB
Overload limit for 0.01% THD @ MM; 110 mV
Overload limit for 0.01% THD @ MC; 8 mV

 

  Again, we have completely gone through this unit as described above. All functions test fine. 
 This receiver looks NEW, works and sounds great! Includes original Box and packing and the originally optional, Yamaha RS-9 Wireless Remote Control. Comes with an 'e-copy', pdf download of the original Yamaha R-8 owners manual. Unit measures 17.2" wide x 5.9" tall x 16.6" deep and weighs 25 lbs unpacked. Includes our standard 90 day limited warranty.
YAMAHA R-8

Cond. 9+

$389.00
(C) R.R.

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)
 


 

 

    

NEW LISTING 3/22/17
(Click on above thumbnails to enlarge photos)
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE SANSUI STEREO RECEIVER
SANSUI 661
#...0083
Circa 1974-76
  "
WORLD AC POWER"
MIJ
SOLD 3/23/17
SHIPPING TO MONTANA

ü  Our technician has completely gone through and 'Certified' this unit.

ü  Everything was cleaned inside and out including all contacts, switches and controls.

ü 
AC voltage selector corrected and correct NEW 'mains' fuse installed

ü  Skewed control shafts straightened

ü  All question-able and common 'stress point' solder joints re-flowed

ü  Bias current adjusted to correct level

ü  DC offset adjusted to a low level ‘0’ mVDC (±10) on either channel

ü  Headphone floor noise tested and found to be very quiet, to MAX volume

ü  We also aligned the tuner for optimum AM & FM performance as older internal tuner components have always drifted on vintage gear over the years.
VERY GOOD TUNER!
AM reception WAY above average, FM reception incredible, PUNCHY, with GREAT SEPARATION and IMPECCABLY CLEAN!!!

ü  All meter, dial, and FM stereo indicator and FM function lamps replaced for trouble-free service

ü  Entire unit cleaned / detailed cosmetically inside and out.

ü  All inputs tested and both sides produce clean and even sine waves into static 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions test fine.

ü  Following restoration procedures, the unit was run continuously at medium volume, as all our amplifiers / receivers are, into a load with "Loudness" on and both Tone Controls at 10 for 48 hours and into a 4 Ohm Load!

We also aligned the tuner for optimum performance on both AM and FM. All functions tested for perfect operation. All inputs tested and both sides produce clean and even sine waves! No power supply hum of any kind. It's dead silent! Tone controls are super quality, Alps brand, "full-size", de-tented potentiometers. All functions tested for perfect operation.

You will not be disappointed. Total restoration time investment ~7 hours.  

Following the above tech work, on our test bench, this unit's amplifiers produced 17.5 volts @ 8 Ω per channel for 38 watts / channel and 14.5 volts @ 4 Ω per channel for 52 watts / channel via discrete, metal cased, TO-3 style output devices at 1khz. (4x Sankyo 2SC1111).
AC idle current draw measured at 0.2A.
DC offset adjusted to 0 mVDC ±10.
Bias current adjusted to 19mA.
Floor Noise Level tested at 2.5mVAC / -58dBm.

This is the mid line for Sansui's receiver offerings spanning 1974-1976. The Sansui 661 Stereo Receiver. Classic looking brushed-aluminum silver face with brushed dial glass with green, back-lit numerals. Matching, milled aluminum control knobs. This particular one looks near new.

Sansui 661 Features include:

 
- Weighted flywheel analog tuning
- A-B, A+B or Off speaker selector
- Separate Bass and Treble
- Built-in Hi filter for reducing 19kHz pilot tone and 38kHz Harmonic in FM broadcasts, Tape Hiss  and any external processor hiss (don't buy noisy / cheap processors and that won't be a problem in the first place)
- FM muting, separate from FM stereo selector
- Stereo / Mono mode selector for Pre-Amp section
- "Loudness" function to boost Bass and Treble in relationship to Mid frequencies at lower volume levels for a much fuller sound.
- Phono / turntable input
- AUX Input (CD / DVD /DAT / VCR / iPod / MP3 / iPod / XM / SIRUS etc.) input
- Dual "True" tape monitors with Tape 1 sporting RCA and DIN I/O's.  (Tape Monitors can be used with Video / CD / DVD / VCR / DAT / iPod / MP3 / XM / SIRUS CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc) Dubbing can be used with CDR (CD recorders) units)
- Tape
dubbing 1 to 2
- VU Signal Strength meter
- 4-Channel Adaptor Loop
- Dual AC convenience outlets on rear panel with 1 switched and 1 un-switched for a total capacity of 250 watts of accessories
- True “
WORLD AC POWER"

   as it will work on both 50 or 60 Hz AC and voltages from 110-240 volts AC

 
Sansui 661 Original Specs:
  
"The Sansui 661 has a continuous power output of 25 RMS watts per channel min. @ 8 ohms from 20 hertz to 20,000 hertz with no more than 0.5% THD (measured utilizing AUX input)"
 
POWER / PRE AMP SPECIFICATIONS:

THD: 0.5% @ full rated power
Freq Response of power amp section:

@ full rated power 30-20kHz
 Potential frequency response of power amp section @ 1w: 20-40,000Hz ±2dB
 
IMD utilizing AUX: 0.5% @ full rated power / 30-20kHz

TUNER SPECS FOR FM:
Freq Response:
30-15kHz
S/N
: > 60db Mono
Mono RF Sensitivity:
2.2 μV
Capture Ratio:
2.5dB
De-Emphasis: selectable 50/75 μ-sec
THD w/ 100% modulation @ 1kHz, Mono: 
0.5%
THD w/ 100% modulation @ 1kHz, Stereo: 
0.7%
FM Alternate Channel Selectivity: 
60dB wide or narrow

PHONO SECTION SPECS:
Freq Response:
30-20kHz
S/N:
70 dB, ref w/ 10mV input
Input Sensitivity:
2.5 mV @ 50kΩ
Overload limit:
150 mV
 
Again, as stated before, we have completely gone through this unit cleaning and testing all. Driver boards serviced and tuner aligned. Brushed aluminum face and all original, milled knobs in fabulous shape. Wood grained, vinyl wrapped case in great shape as well. The unit looks near NEW! After 7 hours technician / restoration time, receiver performs and sounds great! Includes an 'e' copy, pdf download of the Sansui 661 brochure if purchaser desires. Comes with original box and packing. Measures 17.5" wide x 12" deep x 5.25" high and weighs 22 lbs unpacked. Includes our standard 90 day limited warranty!
SANSUI 661
 
Cond. 8.5++
 $379.
SOLD 3/23/17
SHIPPING TO MONTANA

(C) R.R.

 

 
(Above text, in it's entirety, property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

 

 




So, why do the older / 'vintage' receivers and amplifiers sound so much better (for music) than the much more modern and fancier, 'surround sound - 5.1', '7.1', or '8.BR549' A/V receivers? (PART 1)

 Mostly due to Amplifier design and 'Amplification Classes' - All sound is a sinusoidal waveform. It has alternating peaks and valleys. The center point of each wave is the zero, or switching point that separates the positive (top) from the negative (bottom) portion of each wave. When a amplifier operates in 'Class A' , the output tubes or transistors amplify the entire waveform without splitting it into positive and negative halves. In 'Class AB', (used in the majority of classic receiver / amplifier designs), the signal is split into two halves, positive and negative, and each half is sent to a tube or transistor circuit for amplification. Both sides work in tandem, and the two halves are recombined at the output section to reconstruct the whole signal. This technique increases the amount of power that can be applied, but increases distortion.
In many 'modern' A/V and subwoofer amps, 'Class-D' is the dominant design method. Class D operation is essentially a rapidly switching power amplifier. Here the output devices are rapidly switched on and off at least twice for each cycle. Theoretically, since the output devices are either completely on or completely off they do not dissipate any power (heat), greatly increasing efficiency and lowering manufacturing cost thru lesser parts and lighter freight weight. Not musically the best sounding design for listening to standard, 2-channel music (Radio, Vinyl, CD'S, DAT, Tape (not 'crappy' compressed, MP3 formatted files), but popular for 'A/V-Surround-Sound' systems for reproducing 'movie sound tracks' (not too difficult to do from a 'sonic quality standpoint') where slightly elevated levels of distortion are tolerated and for subwoofer use where maximum power is necessary, and slightly elevated levels of distortion are also easily tolerated...Cont in Part 2 (also on this page)

Excerpts of the above text from the website of one of the best Car Audio sites and stores in the world, 'Car-Fi' www.car-fi.com .

  

 

 

Yamaha_R-700_Stereo_Receiver_web-b.jpg     Yamana_R-700_Receiver_Collage.jpg

NEW LISTING 1/7/17
(Click on above thumbnails to enlarge photos)
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE YAMAHA R-700 STEREO RECEIVER
#...0340
Circa '81-'83
MIJ

for sale

Our technician has completely gone through and 'Certified' this unit.
Everything was cleaned inside and out including all contacts, switches and controls. We tested all circuits associated with Yamaha IG04540 'voltage amplifier' pack as well as select resistors and checked for 'leaky' capacitors in the drive circuit. DC offset and bias PC mounted pots cleaned and current adjusted to within spec. Entire unit cleaned / detailed cosmetically inside and out. All inputs tested and both side produces clean and even sine waves into static 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions test fine. Following restoration procedures, the unit was run continuously at medium volume, as all our amplifier / receivers are, into a load with "Loudness" on and both Tone Controls at 10 for 48 hours and into a 4 Ohm Load!

   

On our test bench, each internal amplifier of this particular unit, #...0304, produced peak power of 25 volts per channel for 78 watts per channel at 8 ohms and 21 volts at 4 ohms for 110 watts per channel via dual Yamaha IG 04570 power pack output devices. AC idle current draw measured at 0.4A. Floor Noise Level tested at <1mVAC.
____________________________
  

    
Great Yamaha R-700 receiver designed in the tradition of the classic analog models, but with the convenience of a digital tuner. Very nice looking unit. Classic Yamaha "Satin" finish aluminum face and matching knobs.
Yamaha R-700 Features include:
  
- Digital tuning ('Auto' scanning only. No 'Manual' on the R-700)
- 5 AM & 5 FM tuner presets

- A, B and A+B speaker selector
- Separate Bass and Treble with high quality de-tented controls
- Record Out selector with bi-directional tape dubbing controls. (Separate "Record Out" allows recording from one source while you listen to another)
- Dual tape deck monitors (Tape Monitors can be used with Video / CD / DVD / VCR / DAT / iPod / MP3 / XM / SIRUS CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc)
- Phono / Turntable input with built-in phono pre-amp
- AUX Input (may also be used for Video / CD / DVD /DAT / VCR / MP3 / iPod® / iPad® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS®  etc.)
- Yamaha's exclusive Variable "Loudness" control
- Variable Spatial Expander built-in
- Hi filter for reducing tape hiss / electronic hiss & noise and record static
- Stereo / Mono selector for entire 'Pre-Amp'
- FM muting / FM 'Stereo / Mono' function
- Auto 'Local / DX' selector
- Digital indicators for Station frequency, DX / Local mode, Stereo and Station Lock as well as an LED signal strength meter
- Triple AC convenience outlets located on the rear panel (1 switched @ 200 watts and 2 un-switched @ 200 watts for a total capacity of 400 watts)

   
 Yamaha R-700 Original Specifications:

   
"The Yamaha R-700 has a continuous / RMS power output of 50 watts per channel min. @ 8 ohms from 20 hertz to 20,000 hertz with no more than 0.01% THD (measured utilizing AUX input)"
  
POWER / PRE AMP SPECIFICATIONS:

Freq Response / Bandwidth of power amp section;
@ 25 watts / 8Ω  5-40kHz
THD utilizing AUX;
0.02% @ 25 watts 5-40kHz
Dynamic Headroom; 2.5dB! @ 8Ω
Damping factor; >40 @ 8Ω full bandwidth
Rated Power; 50 wpc @ 8 ohms @ 1kHz
Signal / Noise ratio;  100dB @ AUX / Tape
85dB @ Phono MM
Input Sensitivity AUX / Tape; 17mV
Tape Output level;
  120mV / 470Ω
Bass Control Characteristics;  ±10dB @ 50hz
Treble Control Characteristics;  ±10dB @ 10khz (manual states at 20kHz, but that has to be a 'mis-print. Just FYI per Jerry at www.oaktreevintage.com .)
Treble Filter;  6dB / Oct @ 8khz
Low Filter;  'Automatic' 12dB /Oct @ 10hz
"Loudness" Contour;  Maximum -20dB @ 1khz
  
TUNER SPECS FOR FM;
 
Tuning Range;
87.6-108 MHz
Freq Response;
30-15kHz ±0.5 dB
S/N; > 80db Stereo
S/N; > 84db Mono
50 dB Quieting Sensitivity:
Mono (DX) 3.2μV (15.3 dBf)
Stereo (DX) 25 μV (33.3 dBf)
Useable Mono Sensitivity (98 MHz, 30 dB Quieting);
2.5 μV (300 ohms) 13.2 dBf
1.25 μV (75 ohms) 13.2 dBf
Capture Ratio; 2.2dB DX, 1.5dB Loc
FM Selectivity; 68 dB
Spurious Response Ratio; 100 dB
IF Response Ratio; 100 dB
AM Suppression Ratio; 65 dB
FM separation;  50dB @ 1kHz
Auto DX Threshold; 30 μV / 34.8dB
  
TUNER SPECS FOR AM;
Tuning Range;
525-1605kHz
S/N; > 50db
Useable Sensitivity; 200μV / m with loop antenna
Selectivity; 30dB
Spurious Response Ratio; 50dB
Image Response Ratio; 40dB
  
PHONO SECTION SPECS;
Freq Response;
20-20kHz

S/N @ 5mV / Input shorted;
85dB with MM cart.
Input Sensitivity; 2.5 mV w/ MM
Overload limit; 250 mV
  

Again, as stated before, we have completely gone through this Yamaha R-700, Stereo Receiver cleaning and testing all and it gets our full 'Certification' . All functions test fine, with the exception of the tuning 'memory presets'. They can be a bit 'finicky' on this unit. Most of the time they work fine, but occasionally when you press one, you will get the station a few '10ths' off, ex: if you store "91.50", you might get "91.30" next time you go to that preset. If you press it once or twice more, it usually goes to the correct "91.50". Not likely an issue for most folks, but it's there
Dark Rosewood grained vinyl covered case in great shape as is the brushed aluminum face and matte finish knobs. This receiver looks near NEW, works and sounds great!

Comes with an 'e' copy pdf, download of the Yamaha R-700 users / owners manual. Unit measures 19" wide x 4.75" tall x 13.25" deep and weighs 20 lbs unpacked. Includes our standard 90 day limited warranty.
 YAMAHA R-700 STEREO RECEIVER
 Cond. 9

 
$359.00
 

 
(Above text, in it's entirety, property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

 


 



WE HAVE RECENTLY RESTORED A FEW MID-SIZE TO LARGE POWER RECEIVERS, AND WILL BE POSTING THEM AS TIME ALLOWS OVER THE NEXT FEW WEEKS...
 

 

- - -

 

 



Did you know?

What is the difference between a ‘Tuner’ and a ‘Receiver'?

A ‘Tuner’ is the component or aspect of an audio system that receives or ‘Tunes-In’ Radio Stations.
A 2-channel, stereo ‘Receiver’ is really 3 units in one!
It’s a ‘Tuner’ for receiving radio stations. It’s a ‘Pre-Amp / Control-Amp’ for source / input selection & tone / audio signal modification (with likely the phono 'pre-amp / head-amp' built-in). Lastly it’s a ‘Power Amplifier’ to energize your speakers. It's essentially the 'heart' of most audio / stereo systems.
Some manufacturers would silk-screen 'Tuner-Amplifier' on the front of their receivers, but that was / is simply 'marketing' to make it sound as if it's something more complicated. It's still a 'receiver'. Just FYI.


 
 

 

 

What is a 'Receiver' and how is it different than a 'Tuner' or an 'Amp'?
The term 'Receiver' refers to a combined unit consisting of at least 3 aspects incorporated into one. The 3 basic units are the AM/FM 'Tuner' or radio, a 'Pre-Amplifier' / 'Control-Amp' and a 'Power-Amplifier' all combined in one 'box'. Originally the general consensus was that 'receivers' did not perform as well as 'separates' and were sonically inferior. While this may have been the case early on, as in the

 

late 1950's to early '60's, technology improved quickly and by the mid-late 60's the arguments for separates over receivers for most 'mid-level' consumer Hi-Fi applications were generally without merit. For 95% of home-audio listeners, a receiver will be more than ample.

 


 

 


Click here for our Restoration Procedures



 
- -  

 

Jerry Gahagan of OakTreeVintage
Taken in portion of Speaker Audition Room
Vintage Home Audio Speakers from the late 1960's into the 1980's

 

 

-
SOLD ITEMS BELOW

 



 

 
 


CLICK HERE TO SEE OUR ARCHIVE OF
 SOLD RECEIVERS.
 

WE WILL LIKELY GET MORE OF THEM AGAIN!!!

    

NEW LISTING 5/19/16
  (Click on above thumbnails to enlarge photos) 
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE NAD STEREO RECEIVER
NAD 7140 RECEIVER

#...6031
 Circa 1985-86

SOLD 11/16/16
SHIPPING TO CALIFORNIA

Our technician has completely gone through and 'Certified' this unit. Unit disassembled, then everything was cleaned inside and out including all switches, controls and contacts. Extensive cleaning of unit internally. Controls were 'flooded' w/ 'De-OxId' and are quiet. Internal fuses checked for correct value / function and replaced where necessary. We also aligned the tuner front-end on both AM & FM bands for optimum performance as older tuner components will have 'drifted' over the years. Amplifier section had output bias and DC offset adjusted to spec levels. All indicators checked and are LED's for trouble-free service.
All inputs tested and both sides produce clean and even sine waves into 'brick-wall' 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions test fine, including tuner pre-sets. Following restoration procedures, the unit was ran continuously at medium volume, as all our amplifier / receivers are, into a load with "Loudness" on and both Tone Controls at 10 for 48+ hours. You will not be disappointed.


While this model was originally rated at 40 watts / channel, on our test bench, this unit's (#...6031) amplifiers produced 23 volts per channel at 8 ohms for 66 watts per channel or 20 volts at 4 ohms for 100 watts per channel via discrete, output devices (B688 (x4) & D718 (x4)). 
 AC Idle current at 400mA, Bias adjusted



and DC offset output adjusted to < 1.3 mV DC either channel Floor noise @ <0.1mV AC either channel.

 This NAD is even stable for limited amounts of time into 2 ohms!

   _____________________________



 A classic NAD 7140, Stereo Receiver. NAD gear is famous for very plain, almost military appearances, but solid performance with lots of headroom. I used to sell these new and never remember an NAD owner who wasn't proud to own one. We've had two 7140's and following their service, the tuners performed fabulously, on both AM and FM. AM normally seems to be an 'after thought' on many stereo receivers, but this one tunes like an old, tube, table radio.

  NAD 7140 Features include:
 
- Digital tuning with a PLL circuit that provides 80 dB Stereo S/N
- 5 AM & FM station presets
- LED tuning indicators
- 5-Segment Signal Strength meter
- Auto or Manual Station / Frequency scanning
- Speaker output impedance selector (a very important aspect of this unit. Allows you to get all of it's power into a single pair of 8 ohms speakers if you need it)
- Bridgeable power amplifier
- Output selector for 8 or 4 Ohms speakers (meaning that you can get 100% FULL output into just ONE set of 8 Ohm speakers. All amplifiers / receivers should have this)
- Stereo / Mono selector
- Loudness control
- Loudness Compensation function
- Low-Level EQ compensation switch
- Input for CD
- AUX input for (Video / CD / DVD / VCR / DAT / MP3 / XM / SIRIUS etc.)
- Phono / Turntable input with built-in Phono pre-amp.
- Selectable phono section for MM or MC turntable cartridges (MC head amp provides 20 dB gain)
- Tape monitor (Tape Monitors can be used with Tape / Video / CD / DVD / VCR / DAT / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRIUS® CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc)
- Pre-Amp OUT / Power-Amp IN loop
- Balance
- NAD's "Soft Clip" feature for speaker protection and smoother sound at higher volumes (can be defeated)
- Bass EQ feature provides +6dB @ 32 Hz boost on the low-end
- NAD's "Infrasonic" filter for reducing Turntable / Tone-arm rumble
- 1/4" stereo headphone jack
- 2 Convenience AC outlets (1 switched

Original NAD 7140 Specifications:

"The NAD 7140 has a continuous power output of 40 watts per channel min @ 8 ohms from 20 hertz to 20,000 hertz with no more than 0.03% THD (measured utilizing AUX input) and & 65 wpc @ 4 Ohms at 'max continuous' output"
 
POWER / PRE AMP SPECIFICATIONS:

THD: 0.03% from 250mW to rated output of 40 Wpc @ 8 Ohms
IHF dynamic Headroom at 8 Ohms: +3dB
IHF dynamic MAX short term: 80W @ 8 Ohms, 95W @ 4 Ohms and 110W @ 2 Ohms
'Bridged' power at 8 Ohms: 100 Watts w/ dynamic, short term of 180 Watts
Slew Rate: 20V/usec
Damping factor:
>50 @ 8Ω full bandwidth
Power Amp Input Impedance:
20k Ohms
Power Amp Input Sensitivity for Full Output of 40 Watts:
1V
Tone Control ranges:
Bass:
+/-7
dB @ 100Hz
Treble: +/-7dB @ 10kHz
'Speaker Equalization' (Loudness) control w/ vol @-40dB: +3dB at 70 Hz, +6dB at 32Hz

Input Sensitivity at all inputs except phono & mic:
25mV for 1W output / 150mV for 50 Watts
Input max Voltage (excluding Phono): >10V

Input Freq Response (except Phono & Mic): 20Hz-20kHz
Tape Output Impedance:
1k Ohms
Pre-Amp Output Level Max / Impedance :
10 V / 800 Ohms
Pre-Amp THD @ rated output: <0.04%
Pre-Amp S/N @ 'Tape' & 'AUX': >102dB

TUNER SPECS FOR FM
Freq Response:
30-15kHz (per FCC regulations)
S/N:
 > 82dB Mono @ 75dBf
Useable Sensitivity (IHF):
9.8 dBf / 1.7μV
Capture Ratio:
1.5dB
THD w/ 100% modulation @ 1kHz, Mono: 
0.09%
(2.2 times better than a Pioneer SX-939 for example)
THD w/ 100% modulation @ 1kHz, Stereo: 
0.09%
(4.4 times better than a Pioneer SX-939 for example)
IF Rejection: 
75dB
Stereo Sub-Carrier Rejection: 
60dB

AM Carrier Rejection / Suppression ratio: >65dB
Image Rejection:
75 dB
FM Alternate Channel Selectivity: 
70dB
FM Adjacent Channel Selectivity: 8dB
Stereo Separation:
50dB @ 1kHz (10dB better than a Pioneer SX-939 for example)

TUNER SPECS FOR AM:

RF Sensitivity: 300uV/meter or 15uV @ binding posts
Alternate Channel Selectivity:
35dB
IF Response Rejection Ratio:
50dB
Image Rejection:
50dB

PHONO SECTION SPECS:
Freq Response:
20-20kHz +/-5dB
S/N:
78dB w/ MM cart w/ 5mV & 76dB w/ MC cart w/ 0.5mV
RIAA Response Accuracy:
+/- 5dB

Input Sensitivity / Impedance:
0.4 mV @ 47 for 1 W and 2.5mV for 40 W output
Overload limit:
1.5V

 

 
Again, we have completely gone through this NAD 7140 Stereo Receiver, as stated above and 'certified' it's 'Ready To Go'! Speaker outputs feature heavy duty "banana" / binding post outputs. Includes a pdf, 'e' copy, download of the NAD 7140 owners / users / instruction manual, and brochure. Unit looks and sounds great! Measures 16.5" wide x 15.25" deep x 4.5" tall and weighs 20 lbs unpacked.
 Cond. 9
 NAD 7140

SOLD 11/16/16
SHIPPING TO CALIFORNIA

(C) C.B.S.


(Above text, in it's entirety, property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)
 

 

   

     

NEW LISTING 11/16/16
  (Click on above thumbnails to enlarge photos)
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE PIONEER STEREO RECEIVER
PIONEER SX-980 RECEIVER
HUGE POWER AND SIZE!
#...0902S

Circa 1978-79
MIJ

SOLD 11/29/16
SHIPPING TO FLORIDA


ü  Our technician has completely gone through and 'Certified' this unit. Everything was cleaned inside and out including all switches, controls and contacts. Extensive cleaning of unit internally.

ü  Sheared 'Treble Potentiometer’ and slightly intermittent ‘Volume Control’ replaced with original Pioneer parts.

ü  Intermittent speaker selector repaired

ü  Controls were 'flooded' w/ 'De-OxId' and are quiet (very difficult to do as 'tone' section must be painstakingly removed).

ü  Replacement AC line cable replaced

ü  Switches such as the 'Function' selector and the 'Tone Bypass' switch were also flooded with cleaner.

ü  All control switch / pot shafts checked for ‘true’ (straightness)

ü  Internal fuses checked for correct value / function and replaced where necessary.

ü  “World AC Power” unit correctly set for North American current.

ü  We also aligned the tuner front-end on both AM & FM bands for optimum performance as older tuner components will have 'drifted' over the years.

ü  Amplifier section had output bias and DC offset adjusted to spec levels

ü  We replaced ALL dial, meter & indicator lamps (we had the dial / meter lamps tinted blue), 'Stereo' indicator, AM/FM input / function indicator lamps.

ü 
Both power supply filter capacitors independently tested.

ü  All inputs tested and both sides produce clean and even sine waves into 'brick-wall' 8 & 4 ohm loads!

VERY GOOD FM TUNER!
FM reception as well great and IMPECCABLY CLEAN!!! All inputs tested and both sides produce clean and even sine waves into 'brick-wall' 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions test fine. Following restoration procedures, the unit was ran continuously at medium volume, as all our amplifier / receivers are, into a load with "Loudness" on and both Tone Controls at 10 for 48 hours into a 4 Ohm load. Cosmetically, there are a few, light / shallow striations on the top surface of the face plate edge (like most of the ‘SX’ receivers we’ve had over the years), there’s a ‘thumbnail’ size veneer chip from along the rear, lower edge on one side of the wood veneer case, a few 'tics' around the case, and a small scratch on the tuning knob, but nothing at all distracting (see photos above). Again, overall this is a fabulous receiver. You won't be disappointed. Total restoration time investment ~13 hours.  

On our test bench, the internal amplifiers of this receiver #...0902S produced 29.5 volts per channel @ 8 ohms with 1Khz input for 108 watts and 24.5 volts per channel @ 4 ohms with 1Khz input for 150 watts via discrete outputs with 1 kHz input.
 AC ‘Idle’ current at 420mA, DC offset output adjusted to <2mVDC either channel (that is amazing)(was at -85mVDC on one channel prior to adjustment). Bias current set to Pioneer spec. Floor noise measured .3mVAC / >60dB either channel (was at 132Mvac prior to our refurbishment).
   ____________________________


The
Pioneer SX-980 Stereo Receiver. Classic looking brushed-aluminum silver face and encased in a real wood Walnut veneer cabinet with solid Walnut wood corner caps. These are SERIOUS receivers and as listed above, this one has been 'certified' following the above mentioned refurb by Oak Tree Vintage and is in incredible condition!!! 

Pioneer SX-980 Features:
  - Weighted flywheel analog tuning
 - A-B, A+B or Off speaker selector
 - Separate Bass and Treble with selectable turnover frequency (Treble selectable 2.5k & 5k and Bass 200Hz or 400Hz)
- Tone Defeat selector for purest tone path
- Built-in Hi and Sub filters for reducing 19kHz pilot tone and 38kHz Harmonic in FM broadcasts, Tape Hiss and the Sub filter for reducing turntable rumble
- FM muting, separate from FM stereo selector
- Stereo / Mono mode selector for Pre-Amp section
- "Loudness" function to boost Bass and Treble in relationship to Mid frequencies at lower volume levels for a much fuller sound
- Dual phono / turntable  inputs
- AUX Input (CD / DVD /DAT / VCR / iPod / MP3 / iPod / XM / SIRUS etc.) input
- Dual tape monitors with Tape 2 sporting RCA and DIN I/O's.  (Tape Monitors can be used with Video / CD / DVD / VCR / DAT / iPod / MP3 / XM / SIRUS CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc) Dubbing can be used with CDR (CD recorders) units)
- Tape dubbing 1 to 2
- Microphone input
- -20db Instant Audio muting
- Dual Analog Power VU meters
- Dual tuning VU meters
- Pre-out / Main-in loop
- 25 /75 μsec De-Emphasis selector (on front of unit)
- Triple AC convenience outlets on rear panel with 1 switched and 2 un-switched for a total capacity of 350 watts of accessories


Original Pioneer SX-980 Specifications:

"The SX-980 has a continuous power output of 80 watts per channel min. @ 8 ohms from 20 hertz to 20,000 hertz with no more than 0.05% THD (measured utilizing AUX input)"
 
POWER / PRE AMP SPECIFICATIONS:
THD: 0.050% @ full rated power
Freq Response of power amp section: @ full rated power 20-20kHz
 
Potential frequency response of power amp section @ 1w: 5 Hz to 100 KHz, + 0 dB, - 1,5 dB
 
IMD utilizing AUX: 0.050% @ full rated power / 20-20kHz
Hum / Noise Ratio: 110dB
Damping factor:
30 @ 8Ω full bandwidth
Input Impedance:
50k Ohms
Input Sensitivity for Full Output:
1V
Hi Filter: 6 KHz, 6 dB/octave
Lo Filter: 15 Hz, 6 dB/octave
Loudness Contour: + 6 dB at 100 Hz, + 3 dB at 10 KHz

TUNER SPECS FOR FM:
Freq Response:
30-15kHz
S/N: 
> 74 dB Stereo @ 65dBf
S/N:
 > 80 dB Mono @ 65dBf
Useable Mono RF Sensitivity in dBf:
9.8 dBf
Useable Mono RF Sensitivity in μV:
1.7 μV
Capture Ratio:
1.0dB
Signal for 50dB quieting, Mono:
2.8μV
Signal for 50dB quieting, Stereo: 39.0μV
Signal for 50dB quieting, Mono:
14.2dBf
Signal for 50dB quieting, Stereo: 37.0dBf
De-Emphasis: selectable 25/75 μ-sec
THD w/ 100% modulation @ 1kHz, Mono: 
0.1%
THD w/ 100% modulation @ 1kHz, Stereo: 
0.2%
IF image Rejection: 
110dB
IF Rejection: 
100dB
Stereo Sub-Carrier Rejection: 
65dB
AM Carrier Rejection:
55 dB
Spurious Rejection: 100 dB
FM Alternate Channel Selectivity: 
80dB wide or narrow
Stereo Separation @ 1kHz: 
50dB

TUNER SPECS FOR AM:

RF Sensitivity:
300 uV/meter or 15 uV @ binding posts
Alternate Channel Selectivity: 30 dB
IF Rejection: 40 dB
Image Rejection: 40 dB
Signal to Noise Ratio: 50 dB

PHONO SECTION SPECS:
Freq Response:
20-20kHz
S/N:
76 dB, ref w/ 10mV input
S/N:
82 dB, ref w/ 5mV input
Input Sensitivity:
2.5 mV @ 50kΩ
Overload limit:
200 mV

Huge power supply in the Pioneer SX-980 featuring large power supply filter caps (63WV / 18,000uf) following an incredible power transformer to feed discrete output transistors.
Again, we have completely gone through the Pioneer SX-980 Stereo Receiver, as stated above and 'certified' it's ready to go!
Cosmetically, the real wood Walnut cabinet on this one is in good condition, with only the earlier mentioned chips / tics.
21.75" wide x 17.25" deep x 7" high and weighs 42 lbs unpacked. Includes our standard 90 day limited warranty!
PIONEER SX-980 STEREO RECEIVER
 Cond. 8.5

(C) D.W.

SOLD 11/29/16
SHIPPING TO FLORIDA

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)
 

  

Pioneer_SX-838_Stereo_Receiver_2_web.jpg   

Pioneer_SX838_Stereo_Receiver_Collage.jpg   

NEW LISTING 1/7/17
(Click on above thumbnails to enlarge photos)
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE & BEAUTIFUL PIONEER STEREO RECEIVER
THE CLASSIC PIONEER SX-838 / SX838
#...560M
Circa 1974-76
"WORLD AC POWER" ™
MIJ

SOLD 1/12/17
SHIPPING TO PENNSYLVANIA

ü  Our technician has completely gone through and 'Certified' this unit.

ü  Everything was cleaned inside and out including all contacts, switches and controls.

ü  ‘Questionable’ Bass Control Potentiometer replaced w/ OEM unit

ü  All question-able and common 'stress point' solder joints re-flowed

ü  Bias current adjusted to correct level

ü  DC offset adjusted to super low level of ZERO mVDC on either channel!!!

ü  We also aligned the tuner for optimum AM & FM performance as older internal tuner components have always drifted on vintage gear over the years. VERY GOOD TUNER! AM reception WAY above average, FM reception incredible, PUNCHY, with GREAT SEPARATION and IMPECCABLY CLEAN!!! due to the 'Pair of Dual-Gate MOS-FETS' FM front end and the quality of the restoration.

ü  All meter, dial, function indicator, 'Speaker Indicator' (not an easy task) and FM stereo indicator lamps replaced for trouble-free service (dial / meter lamps ‘blue tinted’ to original color)

ü  Entire unit cleaned / detailed cosmetically inside and out. Only cosmetic issue is that some 'id' info has been 'rubbed / ground' off the top edge of the face plate at sometime in the past (not seen from the front of the unit, only when looking down on it)

ü  All inputs tested and both sides produce clean and even sine waves into static 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions test fine.

ü  Following restoration procedures, the unit was run continuously at medium volume, as all our amplifiers / receivers are, into a load with "Loudness" on and both Tone Controls at 10 for 48 hours and into a 4 Ohm Load!

You will not be disappointed. Total restoration time investment ~13 hours.  

On our test bench, the internal amplifiers of this receiver #...560M produced 23 volts per channel @ 8 ohms with 1Khz input for 66 watts and 19 volts per channel @ 4 ohms with 1Khz input for 90 watts (this unit is slightly stronger, by almost 10%, than the last 2 SX-838’s we had, probably due to the “ZERO DC OUTPUT” mentioned below) via discrete, TO-3, metal cased outputs. (2x 2SA747 & 2x 2SC1116).
 AC Idle current at 400mA, Bias adjusted and DC offset output adjusted to 0mVDC either channel. Floor noise @ <0.4mV AC either channel following refurbishment.
   ____________________________


This is from the series that is commonly referred to as Pioneer's 'Blue Face' receiver offering. Beautiful receiver. Classic looking brushed-aluminum silver face panel, surrounding 'smoked' dial glass, with 'aqua back-lit' enumeration. Only cosmetic issue is that there is a diagonal crack in the tuning window, near the tuning knobs. It’s not particularly noticeable and not distracting. We could address it, but deemed that the increase in final price of the unit would not justify the additional resources. If it were more noticeable, we would have addressed it, and simply reflected that with an elevated final value / price.  All encased in a walnut grain, vinyl wrapped, cabinet with solid Walnut wood corner caps. These are SERIOUS receivers and this one has been 'certified' following the refurb by Oak Tree Vintage and is in great condition!!! 
Pioneer SX-838 Stereo Receiver Features:
 

Tuner features:
- Weighted flywheel analog "slide-rule" tuning
- PLL FM Tuning and 'Dual Mos-Fet' circuitry
- Fully Shielded tuner 'Front End'
- FM Muting Selector (separate from the 'Stereo' selector)
- Dual analog 'Signal Strength' and 'Tuning' VU meters
- FM Detector / 4-channel RCA output
- Dual position FM De-emphasis selectable for 50 or 75 msec
- Built-In AM 'Stick / Bar' antenna 

Pre-Amp / 'Control Amplifier' features:
- A, B, C, A+B, A+C, B+C & Off speaker selector (max 2 pair at a time, just with most all receivers / amplifiers to maintain a 4 Ohm minimum)
- Dual-Band EQ w/ selectable 'centers' (Bass controls centered at 200 or 400 Hz and Treble @ 2.5 or 5kHz) (same EQ as the SX-950)
- Tone Defeat for purest signal path
- Super quality de-tented Tone and Volume controls
- "Loudness" function to boost Bass and Treble in relationship to Mid frequencies at lower volume levels for a much fuller sound.
- Stereo / Mono selector (for entire pre-amp section, not just FM tuner)
- 'Scratch-Filter / Hi filter for reducing tape hiss / electronic hiss & noise and record static
- Built-in 'Low' Filter to eliminate excess rumble from sources such as turntables
- 'Record Selector' allows monitoring of another source, while recording something else
--20dB Audio Muting for instant lowering of volume without adjusting the volume control. Great for ringing phones and cuing a record on your turntable

Pioneer SX-838 Inputs:
- Dual Phono / turntable inputs with Built-In Phono Pre-Amps
- Dual tape monitors with Tape monitor 'B' also featuring a DIN input as well as the standard RCA I/O's
  (Tape Monitors can be used with Tape / Video / CD / DVD / VCR / DAT / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS® CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc)
- Bi-Directional Tape 'Dubbing' capability
- Aux input (may also be used for Video / CD / DVD /DAT / VCR / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS®  etc.)
- Dolby 'Adaptor' Loop can be used as an additional input or as a signal processor loop for EQ, Dynamic Range Expanders, Reverbs, Delays, DBX units, etc.
- 1/4", stereo headphone jack
- Dual Phono inputs with phono 2 doubling
- 1/4" front mounted Microphone input

Other:
- Pre-out / Main-in loop (allows feed to an additional / larger power amp, or to 'direct feed' the power-amp in the receiver with another pre-amp or audio mixer)
- Easy 'Serviceable' internal design
- Triple AC 'Convenience' outlets (1 switched / 2 un-switched) with a total capacity of 300 watts
  - True “
WORLD AC POWER"
as it will work on both 50 or 60 Hz AC and voltages from 110-240 volts AC
 
Original Pioneer SX-838 Specifications:
  "The SX-838 has a continuous power output of 50 watts per channel min @ 8 ohms & 60 wpc @ 4 Ohms, from 20 hertz to 20,000 hertz with no more than 0.3% THD (measured utilizing AUX input)"
 
POWER / PRE AMP SPECIFICATIONS:

THD:
0.3% @ 50 wpc @ 8 Ohms & 0.05% @ 1 wpc @ 8 Ohms
Freq Response of power amp section:
@ full rated power 20-20kHz
 Potential frequency response of power amp section @ 1w:
10 Hz to 70KHz, + 0 dB,- 1 dB
 IMD utilizing AUX: 0.3% @ 85 wpc & 0.05% @ 1 wpc @ 8 Ohms
Hum / Noise Ratio: 110dB (10dB increase over the SX-950)
Damping factor:
45 @ 8Ω full bandwidth (almost double the SX-950)
Power Amp Input Impedance:
50k Ohms
Power Amp Input Sensitivity for Full Output:
1V
Headphone: 4-16 Ohms
Tone Control ranges:
Bass:
±10
dB @ 200Hz or 400Hz
Treble: ±10dB @ 2.5kHz or 5kHz
Hi-Cut / Scratch Filter: -9dB  10
KHz, 6dB/octave
Lo Cut Filter: -8dB / 50Hz, 6dB/octave
Loudness Contour w/ vol @-40dB: +8dB at 100 Hz, +4dB at 10KHz
Pre-Amp Input Sensitivity at all inputs except phono & mic:
150mV
Microphone Input Impedance: 50k Ohms
Input Sensitivity at all inputs except phono & mic:
2.0mV
Input Freq Response (except Phono & Mic): 15-40kHz
Tape Output Impedance: 150k Ohms
Tape Output:
150mV @ RCAs &
30mV @ DIN
Pre-Amp Output Impedance & Level: 1V / 2k Ohms
Pre-Amp THD @ rated output: <0.1%
Pre-Amp S/N @ 'Tape' & 'AUX': 95dB
Pre-Amp S/N @ ''Microphone': 65dB

TUNER SPECS FOR FM

(essentially similar specs on the SX-950 and SX-939):
Freq Response:
20-15kHz
S/N:
 > 70dB Mono @ 65dBf
Useable Sensitivity (IHF):
1.8μV
Capture Ratio:
1.0dB
De-Emphasis: selectable 50 or 75 μ-sec
THD w/ 100% modulation @ 1kHz, Mono: 
0.2%
THD w/ 100% modulation @ 1kHz, Stereo: 
0.4%
IF Rejection: 
100dB
Stereo Sub-Carrier Rejection: 
65dB
AM Carrier Rejection / Suppression ratio: 55dB
Spurious Rejection:
100 dB
Image Rejection:
85 dB
FM Alternate Channel Selectivity: 
80dB
Stereo Separation:
40dB @ 1kHz

TUNER SPECS FOR AM:

RF Sensitivity: 300uV/meter or 15uV @ binding posts
Alternate Channel Selectivity:
40dB
IF Response Rejection Ratio:
85dB
Image Rejection:
65dB
Signal to Noise Ratio:
50dB

PHONO SECTION SPECS:
Freq Response:
30-15kHz
S/N:
>70dB, ref w/ 10mV input
Input Sensitivity 'Phono-1' or 'Phone-2':
2.5 mV @ 50kΩ
Overload limit:
200-250mV @ 1kHz


Most techs, including myself, who have been inside of the various SX Pioneer series receivers, can see quite a few examples of why they believe earlier series are better built than the later series, especially once 1980-81 rolled around. Evidenced by TO-3, metal cased outputs, shielding around the control pots and some sensitive circuit boards to reduce RFI noise, heavier control pots and Molex connected pre-driver / output circuit boards to facilitate future service.
Again, we have completely gone through this Pioneer SX-838 Stereo Receiver, as stated above and '
certified' it's ready to go!
This is the first SX-838 (or any of that series) we've had in quite a few years. Cosmetically, with the exception of the previously mentioned dial window split (see photos above), the unit is in overall, great condition. Unit looks good, works great and sounds HUGE! Includes an 'e' copy, pdf download of the original Pioneer SX-939 (essentially the same as the SX-838, just a bit more power) owners / users / instruction manual, and brochure. Measures 20.5" wide x 16.5" deep x 6.75" high and weighs a HEAVY 35 lbs unpacked. Includes our standard 90 day limited warranty!
PIONEER SX-838 STEREO RECEIVER
 Cond. 8 (due to small crack in dial window)

(C) R.R.

SOLD 1/12/17
SHIPPING TO PENNSYLVANIA


 

(Above text, in it's entirety, property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

  



So, why do the older / 'vintage' receivers and amplifiers sound so much better (for music) than the much more modern and fancier, 'surround sound - 5.1', '7.1', or '8.BR549' A/V receivers? (Part 2)

Cont from Part 1 of; “So, why do the older / 'vintage' receivers and amplifiers sound so much better (for music) than the much more modern and fancier, 'surround sound - 5.1', '7.1', or '8.BR549' A/V receivers?” (excerpts ‘paraphrased’ from …
So, just as importantly as the ‘technical aspects’ mentioned in “Part 1”, it’s ALL ABOUT THE MONEY, and we consumers want things as ‘cheaply as possible’, right…? Yes, we do, otherwise the market place wouldn’t be flooded with ‘cheeeeeeeeeeeeeeeeeeese’ from China (and from any of the other sources that can ‘make it as cheaply as possible). You say, “hold on a just gohl-darn minuite”, it’s the manufacturers fault, they’re the ones making things so ‘CHEAP’. NO, it’s not their fault. They are simply following consumer demands (who vote with their dollars, by continually spending as little as possible over the past generation++) and have no choice (at least in ‘mainstream goods’) but to produce and supply goods for as little ‘end user cost’ as possible,…”The Race to the Bottom”. Sure, we consumers give ‘lip service’ to terms like “high quality” and “good service”, but in the end, as a whole, we go for the cheapest options (one of the reasons service companies ‘outsource’ customer service to India, is that they can’t afford to pay ‘domestic labor rates’. Why not? Because we consumers want our phone / cable / insurance or whatever as ‘cheaply as possible, and we aren’t willing to pay for any better). Hey, I’ve been guilty of it a few times myself, but have learned the hard way (fortunately fairly early on)  to try and avoid that method of acquiring items and / or choosing service providers.
So, historically stereo manufacturers had to be concerned, primarily with ‘paying themselves’ in the end, when they designed / built / produced something. When mfgs start out to design an item for market, they are usually ‘backing into it’ from a projected retail / end user price point (that was not necessarily as applicable ‘back in the day’, which is how we ended up with ‘monster receivers’ such as the Marantz 2500 & 2600, Pioneer SX-1980, Sansui G-22,000 and G-33,000, Yamaha CR-3020 and a couple of others that escape me). There are many costs associated with bringing an item / model to market and getting it to the point where it can actually be purchased by an end user / consumer. These costs are similar no matter what the item, ie; stereo gear, clothes, tools, food, services, raw materials, or any item or ‘widget’. Some ‘added cost’ items have generally remained a constant as a percentage of the overall final price of an item, over the years, such as ‘raw materials’, payroll, capitol investments, packaging, transportation / shipping etc. However, in recent years, especially where ‘stereo receivers’ are concerned, manufacturers have been adding more and more features. Most of these “features” have little to do with improving the ‘REAL’ sound quality of the unit, and more to do with compatibility with extraneous aspects. We play DVD’s thru them that are encoded with ‘Dolby’, ‘THX’, ‘dbx’, 'DVD', ‘Lucas Sound’, ‘Blu-Ray’, etc. and inputs that mention things like “iPhone”, “Android”, “iPod”, “Apple”, etc. All of those things are ‘licensed’ from their respective trademark owners. Not to mention all of those manufacturers are constantly making changes (they tend to like to call them ‘upgrades’) to their products, which means that any mfg utilizing or including that ‘3rd party’ product as a feature in their product must now employ their engineers to modify their designs to ‘play well with others’. Those licenses cost money, and those costs take away from money that could be available to invest in the ‘sonic quality’ of the stereo unit.
Sonic quality is a sum of many parts, but a few are ‘discrete’ output transistors, instead of ‘chip’ outputs. ‘Metal-Cased / TO-3’ output transistors, instead of simply ‘epoxy-cased’ transistors. Larger power transformers, and larger storage capacitors to both make sure you have the available current to do the output transformers justice, and the ‘storage capacity’ to make sure you have enough power in reserve to produce deep, rich bass notes. Other aspects that add overall quality to a unit are the caliber of the switches, controls, contacts, semiconductors and components, shielding around sensitive circuits, internal wiring quality and connector / connections quality etc. Is the unit designed with ‘full size’ potentiometers, secured to the chassis with metal ‘shaft nuts’, or is it designed utilizing very ‘small body’ (read, “anemic”) potentiometers, with their control shafts simply protruding thru a hole in the front and secured only by their solder joints (which means that every time you touch / manipulate a control, you are ‘flexing / stressing’ the solder joints and circuit board). The same goes for the I/O jacks on the back panel. Throughout the unit, most
modern (most of what has been built in the past 25-30 or so years) electronics are built utilizing ‘SMD’ technology (look it up). While ‘SMD’ tech facilitates automated assembly processes (read, “robots”), keeps weight down (means lower handling and shipping costs), utilizes smaller individual components (again, ‘cheaper’ parts), SMD doesn’t generally lend to the improvement of ‘sonic qualities’. In-fact, it is probably THE BIGGEST CONTRIBUTOR to degraded, ‘analog’ audio quality. It’s great for things like calculators, computers, smart phones, appliances, automotive control devices etc (unless any of those units are expected to sound good). However, better ‘audio quality’ requires ‘better current’ (Amperes / Amps). Better current is generally best handled by traditional, ‘full size’ electronic components (the stuff designed, starting from about the 1920 thru the 1960’s, and generally peaking in designs released about 1977-79...at least as far as consumer hi-fi goes). Components such as ‘real transistors’ (or tubes if you’re so inclined), full size, electrolytic capacitors (bigger is generally better for storage, and that’s one of the main jobs of capacitors), ‘full size’ resistors to handle all that current without ‘melting down’ or going ‘up in smoke’, etc. The main reason that modern gear is able to attempt to accomplish the same tasks (and more) than vintage gear is that they convert the signal from analog to digital on the front end, and only at the ‘last minute’ convert it back to analog at the back end. That comes back to the generation plus old arguments of analog vs digital.
And the beat goes on…


 

 

 

    

          NEW LISTING 5/20/16
  (Click on above thumbnails to enlarge photos) 
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE STEREO RECEIVER
YAMAHA CR-820 STEREO RECEIVER 
#...2506
circa 1977-'79

   MIJ!

SOLD 10/3/16
SHIPPING TO MARYLAND

Our technician has completely gone through and 'Certified' this unit, cleaning everything including all switches, controls and contacts for quiet, positive operation.  We also aligned the tuner front-end for optimum performance as older tuner components have drifted over the years. Only issue that seems to be, is the 'OTS' tuning system seems to be only partially working. Most tuners do not have this, and frankly the few by other brands we have come thru, seem to have similar issues. Means when you remove your hand from the tuning knob, the tuner should 'lock', and an LED lights up. The tuner locks in fine to stations, but the LED only lights dimly. Not 'monetarily practical' to chase. All output transistors removed, independently tested on our Huntron Tracker semiconductor analyzer and reinstalled with fresh heat sink compound. Output transistor bias adjusted to correct 08.0mV . Re-tensioned internal fuse holder clips. Re-tensioned tuner string to relieve flywheel binding and re-centered pointer to correct dial position. Balance of tuner string inspected and weak section replaced.
We replaced ALL meter lamps and the dial pointer lamps with new units for trouble-free service. All inputs tested and both sides produce clean and even sine waves into 'brick-wall' 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions test fine. Following restoration procedures, the unit was ran continuously on 'medium' volume, as all our amplifier / receivers are, into a 4 Ohm load, with "Loudness" on and both Tone Controls at 10 for 48 hours. You will not be disappointed. Total restoration time investment ~13 hours.

   
On our test bench, the internal amplifiers of this Yamaha CR-820 receiver #...6787 produced 24 volts per channel @ 8 ohms with 1Khz input for 72 watts and 20 volts per channel @ 4 ohms with 1Khz input for 100 watts via discrete, TO3, metal cased output devices (2x Toshiba 2SB557 & 2SD427 output transistors).
 AC Idle current at .35A, Bias current set to spec of 8mV.DC offset output <9mVDC either channel. Floor noise at <2.3mVAC either channel.

   ____________________________
   
   One of the classics from Yamaha! This is from one of the most sought after Yamaha receivers. Beautiful brushed solid aluminum front panel with analog, slide rule tuning dial. All original aluminum Yamaha knobs intact and in near new condition.
Features are:
   
  
 - Weighted flywheel analog AM/FM slide-rule tuning with lighted dial pointer
   - Separate Bass, Presence (mid) & Treble EQ with super quality de-tented controls
 - Built-in Subsonic Filter to eliminate excess rumble from sources such as turntables
- Hi filter for reducing tape hiss / electronic hiss & noise and record static
   - Features Yamaha's own "Variable Loudness Contour" control utilizing high quality de-tented potentiometer 
   - Instant -20db audio level muting
   - Analog VU meters for tuning and signal strength
   - Stereo / Mono selector (for entire pre-amp section, not just FM tuner)
   - FM Muting
   - LED AFC Station lock & Stereo indicators
   - Speaker selector for A - B, A+B, or Off
 - Aux inputs (may also be used for Video / CD / DVD /DAT / VCR / MP3 / iPod® / iPad® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRIUS®  etc.)
   - Dual tape monitors with bi-directional dubbing
 (Tape Monitors can be used with Video / CD / DVD / VCR / DAT / MP3 / iPod® / iPad® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRIUS® CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc)
   - Phono / Turntable input w/ built-in Phono Pre-Amp
   - Dual 1/4" Stereo Headphone Jacks

  
Original Yamaha CR-820 Specifications:

   The Yamaha CR-820 has a continuous power output of 50 watts per channel min. @ 8 ohms from 20 hertz to 20,000 hertz with no more than 0.05% THD (measured utilizing AUX input)
  
  POWER / PRE AMP SPECIFICATIONS:
  THD; 0.05% @ full rated power
  IHF IMD; 0.05% @ full rated power
  Freq Response of power amp section;
  @ full rated power 20-20kHz
  IHF IMD;
0.05% @ 1 watt / 20-20kHz
 
  Potential power bandwidth power amp section; 10-50,000Hz
   Damping factor; 40 @ 8Ω / 1kHz
   Signal / Noise;  >97dB @ AUX / Tape
   Input Sensitivity AUX / Tape; 120mV @ 45kΩ
   Bass Control;  ±13dB @ 50hz
   Presence Control;  ±13dB @ 3khz
   Treble Control;  ±6dB @ 20khz
   Low Filter; 25Hz @ 12dB / Oct
   High Filter; 10kHz @ 12dB / Oct
   Loudness Control; Variable
 
  TUNER SPECS FOR FM;
Tuning Range;
88-108MHz
  Freq Response; 30-15kHz
  S/N @ 65dBf; > 77db Mono or 73dB Stereo
  Capture Ratio @ 65dBf; 1.0 dB
  THD Mono @ 1kHz; 0.1%
  THD Stereo @ 1kHz; 0.15%
  FM Alternate Channel Selectivity; 75dB
   Spurious Noise Ratio; 100dB
   IF Rejection; 90dB
  AM Suppression; 65 dB

  Useable Mono Sensitivity (IHF); 3.2 μV / 15.3 dBf
  Useable Stereo Sensitivity (IHF); 40 μV / 37.3 dBf
Muting Threshold; 5μV / 19.2 dBf
  Stereo Separation @ 1Hz; 40dB

   TUNER SPECS FOR AM;
   Tuning Range;
525-1605kHz
   S/N @ 80dB / m; >50db
  Useable Sensitivity (IHF Bar Antenna); 49dB / m
  Selectivity; 30dB @ 1kHz
  IF rejection; 55dB @ 1kHz
  THD; 0.4% @ 80dB / m
 
  PHONO SECTION SPECS;
  Freq Response;
RIAA deviation; ±0.5dB
  S/N; >92dB!!!, IHF-A
   Input Sensitivity; 2mV @ 50kΩ
  Overload limit; 120mV @ 1k

 
Again, we have completely gone through this Yamaha CR-820 Stereo Receiver, as stated above and, with the exception of the previously mentioned 'OTS' LED, it's 'certified' and 'Ready To Go'!
Huge, vertical finned heat sinks for great cooling efficiency of outputs. Great sounding 'Phono' section (check the corresponding S/N ration above). Also, check the S/N ratio of the FM tuner in 'Stereo'! The brushed Aluminum face and knobs are in great condition. The vinyl wrap, wood grain case is also in great condition. The unit looks fabulous, works and sounds great! Includes a pdf, 'e' copy, download of the Yamaha CR-820 owners / users / instruction manual. Receiver measures 20" wide x 15.5" deep x 6.5" high and weighs 29 lbs unpacked. Includes our standard 90 day limited warranty.
   YAMAHA CR-820 STEREO RECEIVER
   Cond. 8.5++

(C) R.R.
SOLD 10/3/16
SHIPPING TO MARYLAND

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

 
   

 NEW LISTING 4/29/16
  (Click on above thumbnails to enlarge photos)

CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE REALISTIC STEREO RECEIVER
REALISTIC  STA-2000 / STA2000
Orig Cat #31-2075

  #...7544
  CIRCA 1978

SOLD 8/3/16
SHIPPED TO KENTUCKY

Our technician has completely gone through and 'Certified' this unit cleaning contacts, controls and pots.
Amp has been cleaned inside and out. All internal control pots and switches are super quality. All Dial / Meter lamps replaced as well as the AM Function, FM Function and FM Stereo Indicator checked and or replaced for trouble free service. We also aligned the tuner front-end for optimum AM & FM performance as older internal tuner components have always drifted on vintage gear over the years. The tuner works exceptionally well in our warehouse. Picks up both AM and FM bands way above average!!! All inputs tested and both side produces clean and even sine waves! No power supply hum of any kind. It's dead silent! All functions test fine. 
     
While this unit was originally rated at 75 wpc, on our test bench, this particular unit, #...7544's amplifiers produced 28 volts per channel at 8 ohms for 98 watts per channel & 31 volts at 4 ohms for 126 watts per channel via discrete, TO-3, metal-cased output devices. (NEC 2SB539A & 2SD287A) DC adjusted down to <4mV L&R. AC idle current draw .35A. Floor noise measured at <0.1mVAC.
   ____________________________
   
Up to 1978, this was the pinnacle of Realistic's offerings. The STA-2000. This one also features an exceptional tuner. All the pots, controls and construction quality in general is way above average! It's built like a "brick ____ house"

Realistic STA-2000 Features include:

   
- Weighted flywheel analog "slide-rule" tuning with huge and heavy tuning knob and wide scale window
- Classic brushed Aluminum face panel
- Main & Remote speaker selectors
- Oversized volume control featuring high quality de-tented pot
   - Separate Bass and Treble controls utilizing high quality de-tented pots that are also Left and Right independent
- Pre-Amp / Power Amp loop
- FM Muting
(separate from Stereo / Mono selector)
- Mono selector (for the entire pre-amp section, not just the tuner and separate from FM muting selector)
- "Loudness" function to boost Bass in relationship to other frequencies at lower volume levels for a much fuller sound (careful using this as it's approx a 6dB boost!!!)
- Hi / MPX filter for reducing the 19kHz pilot tone and 38kHz harmonic in FM broadcasts
- Phono / Turntable input
- -20dB Audio Muting
-  Dual AUX Inputs (may also be used for Video / CD / DVD / VCR / iPod / DAT / MP3 / XM / SIRIUS etc.)

- Dual Tape monitors with Bi-Directional Dubbing capability (Both tape monitors feature RCA and DIN I/O's)
  (Tape Monitors can be used with Video / CD / DVD / VCR / DAT / iPod / MP3 / XM / SIRIUS CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc) Dubbing can be used with CDR (CD recorders) units)
-  Dual back-lit, analog VU power meters
- Overload, Thermal and DC short protection built-in
- Analog 'Tuning' Meter for both AM and FM
- Front mounted 1/4" stereo headphone jack
- Speaker outputs via "bare wire" push clips and redundant RCA type
- Externally located main AC protection fuse
- Dual AC convenience outlets on rear panel with 1 switched and  un-switched totaling 200 watts capacity

   
 Realistic STA-2000 Original Specs:
Frequency Response: 15 Hz to 20 kHz ± 2dB
Signal/Noise ratio at AUX input: 75dB
Power Band Width: 20-20kHz
THD: <0.25% @ 75 Wpc
Power:
75 watts per channel
 
PRE-AMP SECTION SPECS;
Freq Response;
20-20kHz
Bass Control Range; ± 10dB @ 100Hz
Treble Control Range; ± 10dB @ 10kHz
Loudness Compensation; + 6dB @ 100Hz
Cross Talk; 65dB
Tape Out Leval; 140mV
 
 
PHONO SECTION SPECS;
Freq Response;
20-20kHz

S/N;
70 dB
Input Sensitivity;
2.2 mV @ 50kΩ
Overload limit;
230 mV
 
TUNER SPECS FOR FM;
Freq Response;
30-15kHz
S/N; > 70db Stereo
Mono Sensitivity; 1.7 μV
Capture Ratio; 1.5 dB
Image Rejection; 80dB
IF Rejection; 80dB

  
Again, we have completely gone through this Realistic STA-2000 Stereo Receiver, as stated above and 'certified' it's
'Ready To Go'! Real Walnut Wood veneer case in fabulous condition as is the milled aluminum face and all original knobs.
Fabulous performer. Again this receiver looks and sounds great! It's ready to go and ready to ROCK! Receiver measures 20.5" wide x 18" deep x 7" high and weighs 52 lbs unpacked. Includes our standard 90 day limited warranty.
REALISTIC STA-2000
Condition 8.5

(C) R.R.

SOLD 8/3/16
SHIPPED TO KENTUCKY




(Above text, in it's entirety, property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)
 

 
    

NEW LISTING 5/12/16
  (Click on above thumbnails to enlarge photos) 
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE FISHER "STUDIO STANDARD" STEREO RECEIVER
FISHER RS-2004A STEREO RECEIVER

 
#...5859
  Circa late 1970's
  MIJ

SOLD 8/24/16
SHIPPING TO CALIFORNIA

 
Our technician has completely gone through and 'Certified' this unit cleaning contacts, controls and pots. Amp has been cleaned inside and out. Only issue, and it's by design, is the the tuner flywheel's on the Fisher 'RS' series, always seem to have excessive 'play' in their bushings, which makes them a bit 'wobbly' feeling when turned. They function as a tuning knob should, just always have a bit of play. All dial / meter & function lamps replaced. All functions tested for perfect operation. All inputs tested and both side produces clean and even sine waves into static 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent!  Following restoration procedures, the unit was ran continuously at medium volume, as all our amplifier / receivers are, into a load with "Loudness" on and both Tone Controls at 10 for 48 hours.

On our test bench, the internal amplifiers of this particular unit  #...5859, produced peak power of 22.2 volts  per channel for 61 watts per channel @ 8 Ω via discrete output & 15.5 volts per channel for 60 watts per channel @ 4 Ω  via STK, 0050 Power Packs (same as Pioneer SX-780)
   ____________________________

  

Great looking Fisher receiver! Beautiful when lit up at night or in a dark room. Classic Silver and Wood look design. Brushed face with milled Aluminum knobs.

Fisher RS-2004A "Studio Standard" Features include:

  
- Weighted flywheel analog tuning
- Speaker Selector A, B, A+B, and Off speaker selector
- 5-Band, Graphic EQ featuring high quality de-tented tone controls (centers @ 50, 250, 1k, 4.5k and 15kHz)
 - Tone Defeat selector for purest tone path
- Rear located, vertical heat sinks to dissipate output generated heat away from the rest of the unit, outside of the case (All gear should be designed this way)
- "Loudness" function to boost Bass and Treble in relationship to Mid frequencies at lower volume levels for a much fuller sound.
- FM Muting
- 25 /75 μsec De-Emphasis selector
- Phono / Turntable Input
- Tuning VU meters for signal strength
- AUX Input (may also be used for Video / CD / DVD / VCR / iPod /
iPhone / DAT / MP3 / XM / SIRIUS etc.)

- Tape monitor
(Tape Monitors can be used with Video / CD / DVD / VCR / DAT / iPod / iPhone / MP3 / XM / SIRIUS etc. and Dubbing can be used with CDR (CD recorders) units)
- 1/4" stereo headphone output on front panel
- Built-in ferrite 'stick' AM antenna
- Rear located main AC protection fuse
- Dual AC outlets (1 switched / 1 un-switched) for a total capacity of 180 watts
 
 
Again, we have completely gone through this Fisher 'Studio Standard' RS-2004A Stereo Receiver, as stated above and 'certified' it's 'Ready To Go'! Brushed Silver face and matching knobs all in great condition. Wood grained vinyl case also in "like new" shape as well. This is a very "Punchy" sounding amp. Tuner performs amazingly well, esp on AM which seems to be often overlooked on stereo receivers. Great headroom and warmth. Unit looks and sounds great. Ready to go! Measures 19.25" wide x 14.75" deep x 5.75" tall and weighs 29 lbs unpacked. Comes with our standard 90 day limited warranty.
 Fisher RS-2004A "Studio Standard" Stereo Receiver

  Condition 8.5

SOLD 8/24/16
SHIPPING TO CALIFORNIA

 


(Above text, in it's entirety, property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 
    

    

NEW LISTING 6/16/16
  (Click on above thumbnails to enlarge photos)
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE PIONEER STEREO RECEIVER
PIONEER SX-1080 RECEIVER
HUGE POWER AND SIZE!
#...0872S

Circa 1978-79
MIJ

SOLD 6/21/16
SHIPPED TO UTAH

ü  Our technician has completely gone through and 'Certified' this unit. Everything was cleaned inside and out including all switches, controls and contacts. Extensive cleaning of unit internally.

ü  Controls were 'flooded' w/ 'De-OxId' and are quiet (very difficult to do as 'tone' section must be painstakingly removed).

ü  Switches such as the 'Function' selector and the 'Tone Bypass' switch were also flooded with cleaner.

ü  Sheared 'Bass Turnover' selector replaced with original Pioneer part.

ü  Bent shaft '-20dB Audio Mute' switch replaced with another original.

ü  Internal fuses checked for correct value / function and replaced where necessary.

ü  World AC Power correctly set for North American current.

ü  We also aligned the tuner front-end on both AM & FM bands for optimum performance as older tuner components will have 'drifted' over the years.

ü  Amplifier section had output bias and DC offset adjusted to spec levels

ü  We replaced light bulbs, including ALL dial, meter & indicator lamps, the dial pointer lamp, 'Stereo' indicator, input / function indicators.

ü  Both power supply filter capacitors independently tested.

ü  All inputs tested and both sides produce clean and even sine waves into 'brick-wall' 8 & 4 ohm loads!

VERY GOOD FM TUNER!
FM reception as well great and IMPECCABLY CLEAN!!! All inputs tested and both sides produce clean and even sine waves into 'brick-wall' 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions test fine. Following restoration procedures, the unit was ran continuously at medium volume, as all our amplifier / receivers are, into a load with "Loudness" on and both Tone Controls at 10 for 48 hours into a 4 Ohm load. Cosmetically, there are a few, light / shallow striations on the top surface of the face plate edge, a few 'tics' around the case, and a small scratch on one of the tone knobs, but nothing at all distracting (see photos above). Again, overall this is a fabulous receiver. You won't be disappointed. Total restoration time investment ~15.5 hours.  

On our test bench, the internal amplifiers of this receiver #...872S produced 35 volts per channel @ 8 ohms with 1Khz input for 153 watts and 32 volts per channel @ 4 ohms with 1Khz input for 256 watts via discrete outputs with 1 kHz input. (4x 2SB701a & 2SD737a).
 AC Idle current at 1.3mA, DC offset output adjusted to <4.3mVDC either channel (that is amazing). Floor noise measured .2mVAC / >60dB either channel.
   ____________________________


The Pioneer SX-1080 Stereo Receiver. Classic looking brushed-aluminum silver face and encased in a real wood Walnut veneer cabinet with solid Walnut wood corner caps. These are SERIOUS receivers and as listed above, this one has been 'certified' following the refurb by Oak Tree Vintage and is in incredible condition!!! 

Pioneer SX-1080 Features:
 

Tuner features:
- Weighted flywheel analog "slide-rule" tuning
- FM Muting Selector (separate from the 'Stereo' selector)
- Dual analog 'Signal Strength' and 'Tuning' VU meters
- FM Multi-Path Detector (handy when installing antenna for best positioning)
- Dual position FM De-emphasis selectable for 25 or 75 msec 

Pre-Amp / 'Control Amplifier' / Power Amp features:
- Direct Coupled (DC) Power Amp architecture
- A or B or A+B or Off speaker selector
 - Defeat-able 4-control / 2-band EQ. (Bass controls centered at 200 or 400 Hz and Treble @ 2.5 or 5kHz)
- Super quality de-tented Tone and Volume controls
- "Loudness" function to boost Bass and Treble in relationship to Mid frequencies at lower volume levels for a much fuller sound.
- Stereo / Mono selector (for entire pre-amp section, not just FM tuner)
- Hi filter for reducing tape hiss / electronic hiss & noise and record static
- Built-in 'Low' Filter to eliminate excess rumble from sources such as turntables
- Pre-Amp Out / Power-Amp Input / Loop

- Dual analog 'Power' VU meters

- -20dB Audio Muting for instant lowering of volume without adjusting the volume control. Great for ringing phones and cuing a record on your turntable

Inputs:
- Dual Phono / turntable inputs with Built-In Phono Pre-Amp
- Dual tape monitors with standard RCA I/O's (Tape Monitors can be used with Tape / Video / CD / DVD / VCR / DAT / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRIUS® CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc)
 - Bi-Directional Tape 'Dubbing' capability
- Aux input (may also be used for Video / CD / DVD /DAT / VCR / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRIUS®  etc.)
- Microphone input (be very careful with your 'home audio' speakers when inserting a mic into any stereo receiver)
- 1/4", stereo headphone jack
- Dual Phono inputs with phono 2 doubling as the Microphone input
- 1/4" front mounted Microphone input
- -20db Audio Muting

Other:
 - Pre-out / Main-in loop
 - 3 AC outlets (1 switched / 2 un-switched) for a total capacity of 300 watts


Original Pioneer SX-1080 Specifications:

  "The Pioneer SX-1080 has a continuous power output of 120 Watts per channel min @ 8 ohms & 150 Wpc @ 4 Ohms, from 20 hertz to 20,000 hertz with no more than 0.05% THD (measured utilizing AUX input)"
 
POWER / PRE AMP:

THD:
0.05% @ 120 WPC @ 8 Ohms & 0.02% @ 60 WPC down to 1 WPC @ 8 Ohms
Freq Response of power amp section:
@ full rated power 20-20kHz
 Potential frequency response of power amp section @ 1w:
5 Hz to 100 KHz, +0 dB, -3 dB
IMD utilizing AUX: 0.050% @
120 WPC 20-20kHz
Hum / Noise Ratio: 100dB
Damping factor:
30 @ 8Ω full bandwidth
Power Amp Input Impedance:
50k Ohms
Power Amp Input Sensitivity for Full Output:
1V
Tone Control ranges:

Bass: +/-7-10dB @ 100Hz
Treble:
+/-7-10dB @ 10kHz
Hi Filter: 6
KHz, 12dB/octave
Lo / 'Sub' Filter: 15Hz, 6dB/octave
Loudness Contour: + 6dB at 100 Hz, + 3dB at 10KHz at -40dB on volume control
Pre-Amp Input Impedance: 50k Ohms
Pre-Amp Input Sensitivity at all inputs except phono & mic: 150mV
Microphone Input Impedance: 50k Ohms
Input Freq Response (except Phono & Mic): 5-80kHz
Tape Output Impedance: 50k
Ω
Tape Output:
150mV

Pre-Amp Output Impedance & Level: 1V / 1k Ohms
Pre-Amp THD @ rated output: <0.05%
Pre-Amp S/N @ 'Tape' & 'AUX': 90dB

TUNER SPECS FOR FM:
Freq Response:
30-15kHz per FCC Regulations
S/N:
 > 80 dB Mono @ 65dBf
S/N: 
> 74 dB Stereo @ 74dBf
Useable Mono RF Sensitivity dBf / μV:
9.8dBf / 1.7μV
Capture Ratio:
1.0dB
Signal for 50dB quieting, Mono dBf / μV:  
14.2dBf / 2.8μV
Signal for 50dB quieting, Stereo dBf / μV:  37dBf / 39μV
De-Emphasis: selectable 25 or 75 μ-sec
THD w/ 100% modulation @ 1kHz, Mono: 
0.1%
THD w/ 100% modulation @ 1kHz, Stereo: 
0.15%
IF Response Ratio: 
100dB
Stereo Sub-Carrier Rejection: 
65dB
AM Carrier Rejection: 55dB
Spurious Rejection:
100 dB
Image Response Ratio:
90 dB
FM Alternate Channel Selectivity: 
80dB
Muting Threshold dBf / μV:
19.2dBf / 5μV
Stereo Separation:
50dB @ 1kHz or 35dB @ 30-15kHz

TUNER SPECS FOR AM:

RF Sensitivity: 300uV/meter or 15uV @ binding posts
Alternate Channel Selectivity:
30dB
IF Response Rejection Ratio:
40dB
Image Response Rejection Ratio:
40dB
Signal to Noise Ratio:
50dB

PHONO SECTION SPECS:
Freq Response:
20-20kHz ±0.2dB
S/N:
76dB, ref 'shorted' input

Input Sensitivity:
2.5 mV @ 50kΩ
Overload limit:
200 mV @ 1kHz


Huge power supply in the Pioneer SX-1080 featuring 4X 71V / 22,000μF power supply filter caps following an incredible power transformer to feed 4 (four) TO-3 output transistors.
Again, we have completely gone through the Pioneer SX-1080 Stereo Receiver, as stated above and 'certified' it's ready to go!
Cosmetically, the real wood Walnut cabinet on this one is in fabulous condition. Face very clean with only the most minor of wear! Unit looks great and sounds HUGE! This is truly one of the "BIGGER BOYS" when it comes to CLASSIC STEREO RECEIVERS! Measures 21.75" wide x 17.5" deep x 7" high and weighs a HEAVY 47 lbs unpacked. Includes our standard 90 day limited warranty!

 PIONEER SX-1080 STEREO RECEIVER
 Cond. 8.5++
SOLD 6/21/16
SHIPPED TO UTAH

(C) R.R.

 

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)
 

 



 



Did you know?
Sansui was founded in 1947, just after WWII as a company manufacturing transformers (one of the most important components of any audio system). During the Sixties they morphed into what would become one of the most well respected companies in quality audio gear. I have owned and sold some incredible Sansui stereo gear from the Seventies and early Eighties. I worked at a Sansui dealer in the early part of the Eighties. Sansui remained a major force in stereo gear until about the mid Eighties, when the vast majority of audio gear started suffering from the 'how cheaply can we get it' syndrome by consumers, thus manufacturers followed suit, by building cheaper and cheaper gear.

 

 

 

    

NEW LISTING 6/16/16
(Click on above thumbnails to enlarge photos)
CheckMarkSmall_web.jpg (792 bytes) warranty
VINTAGE SHERWOOD STEREO RECEIVER
SHERWOOD S-7250-CP
AM/FM STEREO RECEIVER
#...2068

Circa '77-79
for sale
SOLD 7/28/16
SHIPPING TO OHIO

  
Our technician has completely gone through and 'Certified' this unit. Everything was cleaned inside and out including all switches, controls and contacts.
- Internal fuses checked for correct value / function and replaced where necessary.  
- Controls tightened to chassis.
- Amplifier section had output bias and DC offset adjusted to spec levels.  
- All dial / meter illumination lamps were replaced.
- We also aligned the tuner front-end, FM MPX and dial alignment on both AM & FM bands for optimum performance as older tuner components will have 'drifted' over the years. 
INCREDIBLE TUNER! AM reception WAY above average, FM reception incredible, PUNCHY and MUSICAL and IMPECCABLY CLEAN!!!
-
Following above procedures, all functions tested for perfect operation and unit was cosmetically detailed inside and out.  
-
All inputs tested and both sides produce clean and even sine waves into static 8 & 4 ohm loads! No power supply hum of any kind. It's dead silent! All functions tested for perfect operation.  
-
Following restoration procedures, the unit was ran continuously at medium volume, as all our amplifier / receivers are, into a 4 Ohm load with "Loudness" on and both Tone Controls at 10 for 12 hours.
  
On our test bench, each internal amplifier of this particular unit, #...2068, produced peak power of 16.5 volts per channel for 34 watts per channel @ 8 ohm and 14 volts @ 4 ohm for 49 watts per channel via discrete output devices at 1khz. AC Idle current at .3A, & floor noise -60dB. Bias adjusted.

____________________________
  

Beautiful condition, late 70's silver face receiver from Sherwood. Great performance for a 'small-mid-sized' 2-Channel audio system. This is an INCREDIBLEY ‘Musical’ sounding receiver. The tone / pre-amp section very transparent and ‘glassy’ sounding, even with only the FM tuner as a source! Nice looking classic brushed aluminum face and knobs with only minor scuffs. 
Sherwood S-7250 Features:
  
- Weighted flywheel analog slide rule tuning
- A, B, A&B speaker selector
- Separate Bass and Treble controls utilizing high quality de-tented pots
- "Loudness" function to boost Bass and Treble in relationship to Mid frequencies at lower volume levels for a much fuller sound.
- FM Muting (not associated with the 'FM Stereo' function)
- Analog back lit, 'combo' meter for center tuning and signal strength
- Phono / Turntable input with Built-In Phono Pre-Amp
- 'True' Tape Monitor with a DIN input as well as the standard RCA I/O's

(Tape Monitors can be used with Tape decks such as Cassette Tape Recorders/ Players, Reel to Reel's, 8-Track Tape Cartridge Decks, Video / CD / DVD / VCR / DAT / MP3 / iPod® / iPad® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRIUS® CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc)
   - Aux input (may also be used for Video / CD / DVD /DAT / VCR / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRIUS®  etc.)

- Built-in AM ferrite antenna
- Externally located Speaker Protection fuses as well as the AC mains fuse
- Un-switched AC convenience outlet rated to 150 Watts

Again, we have done the previously stated refurbishment / restoration work (~6+ hours) on this unit to insure its performance, and it gets our full "certification". All functions tested for perfect operation. This receiver has an awesome tuner.  All in all it's a VERY 'musical' and 'punchy' sounding receiver / amplifier. Looks NEAR NEW and sounds great! Measures 17" wide x 5.25" tall x 12" deep and weighs an impressive 18 lbs unpacked. Includes our standard 90 day limited warranty.
Cond. 9
SHERWOOD S-7250 STEREO RECEIVER

SOLD 7/28/16
SHIPPING TO OHIO



(Above text, in it's entirety, property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

 

   

We've moved the "SOLD / ARCHIVED" items to their own page.
Click ........HERE.


 


**
"(actual as measured)" refers to original test results done by Hirsch-Houck Laboratories upon test release of product when new. Current "aged" specifications / performance may of course vary from that.

 

 

 

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