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Restoration Steps
 

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

OUR RESTORATION PROCESSES FOR ELECTRONIC EQUIPMENT
AND CLASSIC STEREO GEAR
 

 
These are some of the "how do we" steps in restoring vintage Stereo equipment, audio receivers, tape decks, turntables, radios that we use. Unless a 20-40 year old unit is put through these or similar steps, it will unlikely function to any acceptable / useable level. This is not meant to be instructions, advice, nor in any way, training for anyone not already correctly and competently qualified in electronics repair / restoration.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

WARNING: PLEASE USE CAUTION WITH ANY ELECTRICAL DEVICE. ANY REPAIR AND / OR

RESTORATION SHOULD BE UNDERTAKEN ONLY BY A QUALIFIED TECHNICIAN. THE TEXT'S BELOW

ARE NOT INSTRUCTIONS FOR DOING YOUR OWN REPAIR AND ARE NOT COMPREHENSIVE IN SCOPE.

 

 Due to limited resources we are only able to do restorations / repairs on OUR OWN inventory and unable to take OUTSIDE / CUSTOMER repairs.
If you need work done to your gear,
TRY         SOME         OF         THESE         RESOURCES


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Our Testing and restoration methods:


Receivers / Tuner / Pre-amps Power-amps, Guitar Amps:

     Initial check-in and test for basic function: First check to see that the unit is set for correct North American Voltage. Then we pull the cover / housing and do a visual check for burned components, bad fuses, swollen / leaking capacitors, excessive grime, critters (yes we've found a few mouse nests) and dust or any other obviously problems. We then check for a 'hot chassis', meaning does it have voltage between the chassis, face, knobs etc to ground. We do this because we once had a unit that an 'amateur' had worked on at some time in the past, prior to arriving to us. This person had erroneously connected a wire to a 'hot lug' of the power switch to the chassis, instead of the correct location. Somehow when the unit was powered off, it had 120VAC going to the chassis. Our tech had his hand on the chassis, and reached up to adjust his articulating arm, bench light. He had a full 120 Volts pass from one hand, completely thru him to his other hand. Fortunately, somehow, other than sore arms for a couple of days, he survived unscathed, but technically that was a 'lethal' situation and could have had, and probably should have had much more serious results. We 'dodged a bullet'.
If nothing raises alarm we power up slowly on a Vari-AC to check for any early excessive current draw. At full current after about 10 minutes, we then check for excessive DC 'offset' at the outputs before we connect any test speakers. We then check for AC noise at the outputs. Assuming the unit passes to this point we then evaluate condition of controls, panel lamps, output sine wave quality (using an oscilloscope, an AF gen, appropriate dummy load and volt meter) noting overall quality of the sine waves. Then and only then, do we feel confident to connect to a speaker load for initial 'listening tests'. A piece of gear that has an unusually heavy build up of dust, grease and grime on the output devices and the rest of the circuitry will probably get salvaged even if it does work, as an excessive amount of grime means that the components have been allowed to run hot, thus shortening their life span. Heat is the number one killer of electronics and parts that have an excessive amount of dirt and grime build-up cannot dissipate heat adequately. In addition if you can see that much dirt on the surface, inevitably it has gotten in places where it can’t be cleaned and may cause future problems. Units that have been used in bars, kitchens, garages and shops or in environments with heavy smokers and or lots of dust are to be suspect.

Here is a recent example of two identical models that came in on trade from the same person. He had 'taken the gamble' and purchased one, from a fleeeebay seller who of course said that the unit 'tested fine', 'work as intended', 'sound great', blah, blah blah... He had read about the 'stellar' performance units we had previously had of the same model, and once it arrived, felt that it fell far short sonically, but couldn't 'put a finger' on why. He then tried a second unit from another seller, stating similar condition, with the same results. We don't normally do outside repairs, but since I knew him, and he was local, we agreed to take a look at them, and if nothing else, work a potential trade-in towards one of our 'refurbished' units. After establishing a basic 'state of health', we found that while both were running 'hot', one was running 'scalding' hot (220 plus degrees! at the heat sink). They both did work, and the tuners and all basic functions were there, and they each didn't sound necessarily offensive, but upon further testing into a dummy load and on a scope, we found bias issues. When a basic bias adjustment was initially attempted, neither unit would respond, no matter how far the adjustment pot was 'racked' in either direction with one idling at 63ma!!!.

     <--photos of Sansui units

Both units required EXTENSIVE driver board rebuilds (2-3 hours each of tech time for new capacitors and driver transistors). There were other typical issues that were also addressed, but once done we were able to decrease the temperature down to about 'room temperature' on both. At 220+ degrees at idle, they wouldn't have lasted long, to say the least. Just FYI when you're considering the unit from an 'amateur' electronics seller that says 'it's all good'.


Once we do an initial check-in we vacuum, use compressed air, and brushes to remove all the dust, dirt and grime from the inside of the unit. We strip the unit to the level of cleaning it’s controls and switches, which sometimes even means individually removing the controls from the circuit board completely to do a thorough cleaning. It can sometimes take up to 2 hours just to gain access to clean a units controls.  We also check for obvious past repairs that may not have been done “professionally”. We next check and / or replace any burned or intermittent panel / pilot / meter / indicator lamps. Next any internal memory back-up batteries / capacitors are checked or replaced. We inspect for any “cold” or loose solder joints especially on the input / output jacks and ground / ground-chassis, pots and switches or any other parts that might have force or flexion applied to them. RCA jacks are notorious for developing loose solder joints especially on gear newer than 15 years or so due to manufactures choosing to solder jacks en-mass directly to the circuit boards to save money. Cheaper as it may be, it’s a terrible design that will inevitably fail after just a few uses. The same goes for abandoning the use of quality control pots that use a nut to secure it to the chassis / face-plate. Many units manufacturers switched to using control potentiometers that are soldered to the circuit boards and simply stuck through a hole in the face with no “shaft nut” to secure it. Every time you manipulate the control you stress the solder joint. Some fare well, but most do not over just a few years of use. Two terrible designs that are common on the vast majority of gear manufactured after the early 1980’s but I just had to get on the “Soap Box” about them. We also proactively re-flow most solder joints associated with 'heat' producing components such as 'voltage regulators' and 'power resistors' as even though they may not 'yet' be completely bad, they are almost always in some 'state of going bad soon'.
    
We check tuner dial cords / mechanisms for freedom of motion, frayed tuner string, binding string at flywheel, string slip and alignment, replacing where necessary. We also check tuners on all bands for quality and re-align the tuner "front-end" as most have drifted in performance due to semiconductor age, wear and dirt. Next face plates / housings / patch-bays and knobs are painstakingly cleaned and polished. Entire unit is detailed to look as close to new as practical. Bent control shafts are straightened. Questionable or stiff AC cords are replaced. Wood cabinets are oiled. Loose trim is repaired. The unit is then re-tested for all functions and output quality. Our test for output quality and control potentiometer cleanliness is not simple listening through a set of speakers. We 'look' at the sine waves to make sure the controls are clean. We test one side / amplifier at a time currently. These tests are not to test for "original spec" or deviation from that, but to test the overall health of the pre-amp / power-amp section. We connect the outputs individually to a “dummy load” that can vary from 0-32 ohms. Most amplifiers are tested at both 4 & 8 ohms. We first do an 8-ohm test. In addition to the “dummy load” we connect a calibrated digital volt meter and an oscilloscope to the outputs. To the inputs we connect a sine-wave generator producing a 1 kHz tone with .775 volts output*. We bring the amplifier slowly up to “clip” or to it’s power rails noting that it hits both rails simultaneously. If it is hitting one rail in advance of the other it indicates a bias problem which means that the output devices are either over biased or under biased and will need to be adjusted if practical, or if there's a defective part, it is replaced if practical.  

     Either problem can and usually does result in outputs either running too hot (which shortens their life drastically) or running too cold which will usually result in a “mushy” sound with no "punch". If the signal looks good we note the voltage output and do the math to figure "peak" wattage (you can use the voltage / load figures to deduce RMS output if you wish). We then lower the load impedance to 4 ohms and repeat the tests and then on to 2 ohms if the amplifier is designed to run that low. We also manipulate the controls with the sine-wave to check for dirt induced static as smaller amounts will show up readily on the scope, but may not be heard readily with your ears. If there’s a problem we re-clean or replace the controls and re-test. We then re-assemble the unit completely and it goes to another test bench. Here it is hooked to a signal (usually utilizing the tuner with a quality antenna) and to a pair of speakers. All the tone controls are maxed and the Loudness control (if available) is engaged. It is then “burned-in” for a period of not less than 12 hours at a moderate volume ( and sometimes up to 72 hours) to check for any intermittent / heat related problems. Once it passes all of the above tests it is tagged and bagged to await shipment. (*We choose the “1 kHz into one channel at a time” testing method as we believe it provides greater accuracy as to the health of each channels output section. The alternative and other extreme would be to load both channels simultaneously with full bandwidth pink noise or 1k and then do the measurements. It is difficult, if not almost impossible to tell when pink noise is truly clipping and you can’t check potentiometer condition using this technique. While the latter technique would put the power supply to a more difficult test, outputs are more likely to have issues than power supplies. Neither test is by any stretch of the imagination “real world”, but the 1 kHz lets us get a good bench mark of the performance and check for control condition / quality. The published rating of the amp will usually be about 50-80% of what we will measure it using our method. It would be 1 to 2 times what you would see on the bench using the pink noise method. These methods can be subject to modification.)
Guitar amps get most of the same procedures listed above, but in addition we check, record 
and/or replace all the tubes (where applicable) and test / replace all electrolytic capacitors, especially the filter caps. Reverb tanks are checked for any internal damage, all fasteners are checked for tightness, speakers are tested for quality / problems, cabinets are checked for soundness and amp is test played extensively for sound quality, tone and gain. Definitely one of the more fun parts of the job.


Tape Decks (Cassette, 8-Track, Reel to Reel, etc):

     Initial check-in and test for basic function: First check to see that the unit is set for correct North American Voltage. Then we pull the cover / housing and do a visual check for burned components, bad fuses, excessive grime and dust or any other obviously problems. Assuming the unit passes to this point we then evaluate basic function of the deck playing first a generic tape through the transport to make sure it doesn’t have a habit of eating tape and to check that the transport is engaging all of it’s functions. We then check playback with test tapes noting sound quality on both channels and accuracy of speed. We then attempt a simple record test to see if the unit is at least imprinting a signal onto the tape and then if it will erase it.
Once we do an initial check-in we used 40-60 lbs of compressed air, vacuum and brush all the dust from the inside of the unit. We strip the unit to the level of cleaning it’s controls and switches, which sometimes even means individually  removing the controls from the circuit board completely to do a thorough cleaning. It can sometimes take up to 2 hours just to gain access to clean a units controls. We check and either re-condition or replace all rubber components. This is critical and usually the most time consuming part of tape deck repairs. We’ve all seen what happens to a rubber pencil eraser after just a year or two. It gets glazed on the surface and slick and will not erase anything as it just slides across the paper. Or rubber can revert back to it's original state, sort of a "gooey tar" substance. The same thing happens to all the belts, tires, wheels and rollers in a tape deck or VCR       . Fortunately it takes longer than a year, but it does typically appear after about 8-12 years. Even if a deck is left wrapped in it’s original packing and never used it will likely meet the same fate. In fact that would probably be worse than using a deck everyday. If a deck is used very regularly the rubber parts seem to have less opportunity to glaze up. We stock hundreds of belts and tires, but even then we only have about a 25% (that’s one out of 4 ) chance of having or even having access to the correct replacement rubber parts. Manufacturers of rubber parts are supporting cassette, reel to reel and 8-track cartridge technology less and less all the time due to lack of popularity. Internal tires that are still potentially serviceable, are resurfaced / reconditioned. If they are too far gone, they are sent out to be rebuilt. AC floor noise measured and noted. We also check for obvious past repairs that may not have been done “professionally”. We next check and / or replace any burned or intermittent panel / pilot / meter / indicator lamps (commonly we replace them 'proactively', regardless if they currently function or not). We clean and re-lubricate the transport mechanism. This commonly requires a complete disassembly of the transport mechanisms moving parts. Cleaning a transport on a reel to reel can sometimes be akin to cleaning the dried grease from under a 20 year old automobile. Very commonly the lubes / grease has hardened and must be scraped off parts. Many times, bushings will be "frozen" on a shaft and must be heated just to separate the two parts before cleaning can even begin. No amount of lubing over a varnished joint will bring it back. They must be disassembled, cleaned of all old lube and correctly re-lubed. Auto-Stop mechanism wires are disassembled and new 300,000 or 500,000 silicone damping gel applied. Capstan's are cleaned / burnished. Flywheel bearings likely re-lubed.

One issue specific and common to many of Akai Reel to Reel decks are disintegrated 'transport cams'
on Akai models such as, but not limited to, Akai 1722W, 1722-II, X-150D, X-220D, X-1800SD, 4000, 4000DS, 4000DB, GX-4000 and many more.

We inspect for any “cold” or loose solder joints especially on the input / output jacks and ground / ground-chassis, pots and switches or any other parts that might have force or flexion applied to them. RCA jacks are notorious for developing loose solder joints especially on gear newer than 15 years or so due to manufactures choosing to solder jacks en-mass directly to the circuit boards to save money. Cheaper as it may be, it’s a terrible design that will inevitably fail after just a few uses. The same goes for abandoning the use of quality control pots that use a nut to secure it to the chassis / face-plate. Many units manufacturers switched to using control potentiometers that are soldered to the circuit boards and simply stuck through a hole in the face with no “shaft nut” to secure it. Every time you manipulate the control you stress the solder joint. Some fare well, but most do not over just a few years of use. Two terrible designs that are common on the vast majority of gear manufactured after the early 1980’s but I just had to get on the “Soap Box” about them. We also proactively re-flow most solder joints associated with 'heat' producing components such as 'voltage regulators' and 'power resistors' as even though they may not 'yet' be completely bad, they are almost always in some 'state of going bad soon'.  We then clean the heads and adjust head azimuth w/ a 10kHz, factory azimuth tape and an oscilloscope for maximum accuracy, phasing, output and sound quality. Next we completely demagnetize the heads, capstan and entire tape transport. Reel brakes are adjusted on reel-to-reel decks. If the service is on an 8-track, we will disassemble the track indicator and head track slide, to clean and re-lube and burnish or re-spring the contacts for trouble free service. We will also use factory 8-track service tapes to adjust for cross-talk which is a common problem. 8-Tracks also commonly will have their capstan flywheels remove to remove the old varnished lube, and re-lube. Transport has any necessary adjustments made and lubricated where applicable. 
If the unit being serviced / refurbished / restored is a Reel to Reel deck, reel hub force is measured and adjusted, as well as tension arm springs, pinch roller force and motor 'back torque' using appropriate scales (commonly in 'Dynes' or 'Newtons').
Most 'record capable' types of tape decks will need their internal 'record / play' slide switch extensively cleaned to eliminate many issues.
 
 
Next we test record using a fresh, high quality tape looking for large discrepancies in record / play-back meter levels. We also re-test for speed accuracy and make any necessary adjustments that are available. WE HAVE NEVER DONE THE INITIAL TESTS ON ANY TAPE DECK WHERE WE HAD A DECK BE "ON SPEED", OR EVEN A USEABLE LEVEL OF "CLOSE". R2R's are usually 20-120 cycles low at 1kHz, but can occasionally be sharp by as much as 30 cycles (some late 60's-early 70's decks have actually been 150-300 cycles low!). Consistently, or at least 95+ % of the time, cassette decks are 35-45 cycles over 1k after reaching operating temperature. All the tape deck techs here (including myself) are musicians and know what this means. This means that if you try and use a cassette deck (or any tape deck for that matter) that has not been speed checked, and it is 35-45 cycles "sharp" @ 1k, that is almost a entire "half step" sharp (ie; if a song was recorded in the key of "B", it will play back at a "C"). Try and match with your old studio tapes to your voice or currently tuned instrument at A440. Ain't gonna happen! We strive to adjust our decks to within +- 1cycle @ 1kHz and are usually successful. This requires a "factory" or verified test tone tape, a calibrated frequency counter, lot's of patience and the knowledge of how to make the necessary internal adjustments.
Next face plates / housings / patch-bays and knobs are painstakingly cleaned and polished. Entire unit is detailed to look as close to new as practical. Bent control shafts are straightened. Questionable or stiff AC cords are replaced. Wood cabinets are oiled. Loose trim is repaired. The unit is then re-tested for all functions.
Once the mechanical items and issues are addressed, the internal controls are set to optimize meter levels, PB and Rec levels, and any other levels that are practical. We then do many test recordings using fresh, new (we have a stock of sealed, never used tape for our own use) tape. Playback is tested with known quality and factory test tapes. Cross-talk is checked with a factory 'cross-talk' test tape. If the deck is a "record capable" unit, then recordings are made on both Normal and Hi-Bias tapes for comparisons and are also made at multiple signal levels and with the decks NR features on and off. We look for dB level similarities upon playback and utilize an oscilloscope to monitor the deviation of the original 1k signal and the recorded signal on each tape type. We also then make multiple recordings from CD material that are audiophile worthy (many CD's aren't). As with all our units, the entire "pre-test" and "post-test" procedure is logged in detail in a report we keep on file.
(PS. If you're looking at auctions for 20+ year old units, and someone says, "this tape deck (substitute VCR, Turntable, CD player, Clock or other electro-mechanical device) has never been used or taken out of the box" or, "was used for a couple of hours when new, and has been in the closet ever since" those are BAD THINGS! Probably one of the worst things that can happen to an electro-mechanical unit such as a tape deck, turntable, VCR, etc. is for it not to get used. Just like a car that runs bad after it sits for a few weeks or months, a stereo component can have similar symptoms. Think of how bad the car would run if it hadn't been started in 15 or 20 years! On tape decks, Turntables, VCR's etc. that have been allowed to sit unused, the rubber parts / belts stiffen into one shape and the lubes congeal or worse yet turn to varnish, "freezing" moving parts solid! So the next time you hear, "it's new in the box and was never used" when referring to an electro-mechanical device, think twice and "run like h_ll".)


  Photo is of a Teac 4010S having typical Main Capstan Belt change and Pinch Roller Arm re-lube operation. Not an operation too many folks want to undertake. This is just a couple steps of MANY that is required to try to get most decks back to a level of condition that will allow it to operate for any length of time! Just FYI.

Speakers:

     Each speaker first gets a visual inspection for bad surrounds, dust cap condition, cabinet joint integrity, connector condition etc. After some pre-testing of the individual drivers, any speaker that comes in with drivers (especially woofers) featuring foam surrounds has the foam replaced on those drivers, except in very rare cases. We do this regardless of how "good" the foam may still "look" on a driver. We learned this the hard way as that long ago when we first started in the "vintage" biz, we would "pass" speaker with drivers that had foam that "looked" fine. 100% of those 6 or 7 times we sold speakers that way, the customer called within a day or two of using them to let us know the foam had failed, so they had to be shipped back for re-foaming anyway. (By the way, the truly 'correct' method of re-foaming / replacing speaker surrounds, especially on drivers larger than about 6", and on certain drivers smaller than that, is to 'shim the voice coil'. This requires removing the dust cap. Yes, it's difficult and potentially damaging, but you just need to be careful and methodical. If that is not done, there are two alternative methods to 'centering' to voice coil. The first is 'by feel'. VERY inaccurate and generally only successful by SHEER LUCK. Kind of like setting the timing on your engine 'by ear'. Yes, you MIGHT get close, and the end result MIGHT be a better running engine, but it probably won't be nearly as correct as using the correct equipment. The other method of centering the voice coil involves sending a VERY low frequency tone (DC or approaching DC) to the voice coil to keep it centered in the gap and keeping it there while the glue sets up / dries. Firstly, few folks have the ability or equipment necessary to do this, and secondly, I wouldn't want DC, even at lower power levels, to be sent to my voice coils for extended periods of time to 'cook them'. (an alternative method to the 'DC' version is to raise the frequency to as much as 400, but then you have a 'vibrating' cone that makes 'weighting' the foam all the way down on the cone nearly impossible, which will likely result in a glue joint with 'gaps' and unnecessary glue mass). I am amazed at the lack of credence given to this issue with firstly the folks selling re-foam kits, and secondly the general public installing them. A few years ago, most kits and instructions would include the necessary shims, replacement dust caps, and information on how to remove your dust caps, shim the voice coils and replace the dust caps. Now I am not aware of any that do! Maybe it was causing too many 'customer service' issues / 'call backs' and maybe folks were ruining their drivers removing the dust caps. I can only speculate but it's a shame, as it's a disservice and a misfortune that probably many drivers are likely 'ruined' by incorrect re-foam jobs. There's not a 'pretty' fix I suppose, but if doing the job correctly is beyond someone's capability, then the drivers should be sent to a 'competent' repair shop (competent meaning a shop that correctly 'shims the voice coils') and have them done there)
The units are then disassembled where practical to inspect for physical condition of drivers, crossovers and type / quantity dampening material. You would be surprised at what we’ve found in some speaker cabinets. Everything from rusty speaker frames and motors, exploded caps in the cross-over that have sprayed “shrapnel” throughout the inside of the cabinet, charred / burned crossover networks (speaker may still work, with a crossover that looks like it's been barbequed), mouse nests and once, even a Black Widows web with resident about the size of a quarter still alive and well. Not sure what she had been eating in there.
We next check for driver spider (not the same as the above mentioned, but an actual part of a speaker) attachment and lead wire integrity. We also check for loose internal wiring / connections. Drivers are then re-installed adding or replacing gasket material with fresh. We also add fresh gasketing material to the rear panels / baffle boards where applicable. Once the drivers are re-installed the entire speaker system / cabinet is 'vibration' tested with 'drop tests', mallets and an amplified AF sweep (this is where we almost always find issues, many of where were probably there from the original manufacturer!). Next each speaker is individually tested. We use a pink noise generator as testing with music material from a CD or other similar source will many times not alert you to Tweeter, Super Tweeter open coil issues or other "balance" problems. The PN generator will also alert us to any 'phase' issues, not only between the L & R drivers, but within a cabinet, between woofer and midrange. This is one place that I commonly have to 'triple and quadruple check' my technicians on, as it's any easy one to overlook on 're-assembly' after they've spent hours working on a speaker. The PN generator is also how we find most issues with driver attenuators both prior to and after cleaning (and pretty much all have contact issues prior to our refurb).

Many speakers may sound OK with recorded material, but can have their upper-most-frequency drivers bad. We then test the entire speaker cabinet with it’s components in-place with a sweep tone generator at low, medium and high volumes to check for any buzzing, rattling, extraneous vibrations, air leaks / 'whistles' (commonly found from 80Hz down to 20Hz or so) or sympathetic harmonic tones. We recently had a pair of Pioneer HPM-100's that we came in with three 'hidden / not-apparent' issues. One was a 'blown apart' capacitor on the crossover (all the drivers still functioned, and that would not have been discovered, had we disassembled the speaker), and the second issue was one of the tweeters had a 'buzz' we found during a 'sweep' from approx 2.3kHz down to about 900Hz. We substituted another (after ordering from an on-line auction seller (you guess which 'on-line' auction) and waiting for it to arrive), and it also had a similar 'buzz'. We were then forced to take one from a Pioneer HPM-100 in our personal collection, and yes, it worked fine. The EXACT same scenario happend with one of the 'Super Tweeters', except that it worked 'intermittently' when removed and had the case 'flexed'. That cost's us over $200 just in tweeters, and while most folks may never have noticed the issue, IT WASN'T RIGHT, and had to be addressed. We also replaced the crossover (actually was quicker and easier to replace in it's entirety, then to just replace the blown cap).
We then test both speakers as complete assemblies with pink / white noise to check for driver balance between the two cabinets. This is not only an audible test, but we are able to view the results with our 1/3 octave, 31 band RTA with calibrated mic that registers 20-20kHz. Next a number of recorded selections / cuts for sound quality (another fun part of the job).
Entire unit is then detailed to look as close to new as practical. New, felt feet are usually installed and any grill issues are rectified as practical. Where applicable we oil wood cabinets, lightly repair veneer, then bag and tag them to await packing (which is very difficult to do correctly) for safe transit for shipment. Recent and past speaker technicians include Camerion Gholson, Mark Vandergift, Shane Thurston and John Wright.

                                    (BATCH OF SPEAKERS AWAITING RESTORATION)

Turntables:
 

     We first do a visual check of the table and cartridge / stylus if applicable. If it’s a belt drive table we see if the belt is still intact, missing or on occasion a natural rubber belt will have disintegrated and wrapped itself around the motor capstan thus burning up the motor as it could no longer spin due to the excess rubber around it (we recently had a Philips turntable with this condition. Fortunately the motor was still fine once the rubber ‘goo’ was cleaned / removed and motor was re-lubed).
We check the tone-arm Gimbal bearing for freedom of movement and the arm lift mechanism for smooth operation.
We check the ‘oil / fluid damped’ cuing for correct lift / set-down speed, and if necessary, disassemble, clean and re-invigorate with 100,000, 300,000 or 500,000 silicone damping gel (post tests determine if the gel weight is correct).
We then remove the platter to measure for a new belt and to lubricate the motor, to check / replace any thrust bearings, and clean and re-lubricate the spindle bearing.
We inspect, clean and re-lube any ‘auto-arm’ mechanics. This is usually the most time consuming and ‘risky’ part of any turntable restoration. Most are ‘fairly complicated’ internal workings, with many moving parts that react with other parts, dependent on MANY points to be clean and we lubricated. We recently had one require 20+ hours to rehabilitate! More typically they require 4-8 hours to address ‘auto-arm’ mechanics, especially on ‘mid-1970’s’ tables and earlier.

   

     Pioneer PL-50 in restoration process.

Once the mechanics are complete, we move on to the electronics / sonic aspects.
We check the patch cables if permanently attached for condition, correct resistance and replace / ‘up-grade’ where necessary.
If the patch cables / interconnect cables are ‘detachable’, we check the integrity of the RCA jacks and re-flow solder joints as necessary.
We then make any necessary repairs to the base and when practical to the dust cover and check it’s ‘hinge’ condition for joint issues and ability to ‘hold’ dust cover up-right, adjusting if necessary, and when possible.
We then install a “demo / test” cartridge / head-shell to put the table and all it’s mechanisms through their paces and make any necessary adjustments / parts replacements.
We then check for speed deviations, and correct where necessary / practical / possible. While we strive to get an end result of 99%, +/- 1%, some tables will not allow closer than 95% speed accuracy.
Once we are satisfied the mechanics of the table are operating correctly, we then test for proper and adequate ’60Hz Ground’ correcting where necessary and improving it internally when possible.
We check, test and adjust any internal ‘muting’ micro / reed switches.
We then remove the “tester cartridge”, replacing it with the 'intended' cartridge and optimizing the tone-arm for it checking ‘overhang’ and adjusting through gram weight range, and making sure that ‘anti-skate’ calibration is similar to what it’s indicators state.
Then we use various test LP’s through speakers and a Dual-Trace oscilloscope (on the mid-upper end price range tables we sell) to adjust for anti-skating and cartridge cross-talk, tracking capability, distortion from one channel to the next, and check for the cartridges ability to track test records correctly on signals that are recorded progressively louder. This is sometimes referred to as a ‘cartridge obstacle course’. We may utilize a ‘blank slate’ record to adjust anti-skating / bias (we’ve found it’s the most accurate way, even over our O’scope / test record method). We also generally make notes as we go through turntables recording what the end results of many of the operations / tests were.
We then clean and polish the cabinet and dust cover as much as is practical. When ‘monetarily practical’, dust covers are brought to near new condition. Our guy is amazing with them.
Any dustcover cracks (usually near the hinges) are ‘welded’ for structural integrity. Entire unit is detailed to look as close to new as possible / ‘monetarily practical’.
Any base / case issues are addressed prior to re-assembly.
The tables are then bagged and tagged to await packing (which is no easy task on a turntable) for shipment.

Turntables are one of the most difficult items to pack for safe shipment and streamlined ‘re-set-up’ once the table arrives. That is for another discussion / page.



Here's an example of what our turntable tech can do for the cosmetics alone:       
  (click on thumbnails to view photos)

(PS. If you're looking at auctions for 20+ year old units, and someone says, "this tape deck (substitute VCR, Turntable or other electro-mechanical device) has never been used or taken out of the box" or, "was used for a couple of hours when new, and has been in the closet ever since" those are BAD THINGS! Probably one of the worst things that can happen to an electro-mechanical unit such as a tape deck, turntable, VCR, etc. is for it not to get used. Just like a car that runs bad after it sits for a few weeks or months, a stereo component can have similar symptoms. Think of how bad the car would run if it hadn't been started in 15 or 20 years! On tape decks, Turntables, VCR's etc. that have been allowed to sit unused, the rubber parts / belts stiffen into one shape and the lubes congeal or worse yet turn to varnish, "freezing" moving parts solid! So the next time you hear, "it's new in the box and was never used" when referring to a mechanical device, think twice.)

Effects, Tuners, EQ’s and other signal processors receive much of the same attention as the afore mentioned units.


Vintage radios:

     We first do a visual inspection of the chassis and cabinet. We then remove the chassis from the cabinet and do a visual on the circuitry. We note weather the tubes that are in the sockets are the correct units. Many people will stick a tube into a socket because it fits and looked the same or it’s what they had around. That usually spells smoke and disaster for the radio and certainly the tube and on occasion the operator. We look and see if any of the filter capacitors are swollen or leaky. We also inspect the AC cord to see if it’s safe enough to at least test the unit with. If everything looks in order we then apply AC power slowly to the chassis with a vari-ac noting current draw. Sometimes by the time we get up to only 20 or 30 volts a radio will start drawing ½ - 2 amps and we know we have a problem. Sometimes they will power up fine, but just buzz loudly. Sometimes they start working with only the normal 60 cycle hum from an aged power supply filter circuit. Once we deduce the initial electronic condition of the chassis we then cut the power to the radio. We next remove all the tubes, noting their correct location, test them, record the findings on the tube with a sharpie or replace them where necessary (we also test the new ones as we have had plenty that were bad out of the box). We then clean the chassis completely including all the tube sockets. We next check and almost always replace all the electrolytic filter capacitors as well as checking all the other caps. We then clean all the controls, switches, contacts and the variable tuning capacitor as well as lubricating any moving parts. We then check the dial cord and mechanism for integrity. We replace the pilot lamp and any other light bulbs. We next install a new polarized AC cord and add a fuse for safety. We then install all the tested / replaced tubes and again slowly power the radio up through the vari-ac. After a couple of minutes warming up at this point they usually sound like new! We then disassemble the cabinet thoroughly cleaning the dial glass and cleaning and polishing the housing and knobs where applicable. Entire unit is detailed to look as close to new as practical. We then re-assemble the entire radio and test play for at least 2 hours. They are then bagged and tagged to await packaging for shipment.

Vintage electric fans:

    Fans are very labor intensive for us. That is why we are slow to replace sold units. Each fan is initially tested, if they appear safe, for function, spin balance, oscillation (if applicable), speed switch function and excessive rattles or noise. We are also looking for speed and the amount of time the fan may take to come up to speed. We then completely disassemble the fan and all it’s components. We remove and clean any dried lubricant from the oscillation mechanism (where applicable) and re-lubricate it. We also try and replace any missing / broken parts to the oscillator. We then clean and check the motor and it’s windings. We also check the brushes at this point. We then check the condition of the speed / on-off switch and repair as necessary. We next check the condition of the cage (blade guard) inspecting for broken welds and straightening any bent sections. We then either clean and polish the existing finish or often will sand the unit down and refinish it. We will also at this time polish the blades if they are not painted models. Entire unit is detailed to look as close to new as practical. Once the finish work is complete we will then reassemble the fan installing a new AC cord at that time. The blade is then balanced for the most vibration-free operation possible. We will then run the fan for at least an hour to make sure it is ready to go. We then bag and tag it to await packing for shipment.

Guitars: 

     We have been doing guitar set ups and repairs for almost 20 years for the general public. 
Everyone has their idea of what “Plays great” means, but our set-up will please 90% of Professional players. We know how to assess fret wear, tuner condition, neck relief and electronics. We also are familiar with the different aspects of tone and sound that make, model, strings, pickups, wood and etc can have. We check for fret wear, adjust neck / body angle if necessary, adjust neck relief to correct amount, adjust pick-up height, saddle height, check nut grooves for correctness, disassemble-clean-re-lube tuning machines when applicable  , install new strings, adjust intonation for installed strings, check for excess buzzes and test play the instrument. We also clean and polish the instrument, oil the fingerboard, polish the frets, lube the tuners (if applicable) and make any necessary electronic repairs. If a buyer prefers we can do a custom set-up for their playing style and choice of strings.


Keyboards:

      Each keyboard is initially inspected for performance. We then disassemble the unit inspecting for battery leakage (common), condition (most keyboards utilize a lithium battery for the memory which generally have a lifespan of 3-7 years, and since most vintage keyboards are pre 1990 they almost all need the batteries changed to function), corrosion, bad contacts etc. We will thoroughly clean it inside and out. We then adjust / replace / repair the key contacts, level the keys (if applicable and when practical), check tune, replace any bad tines / reeds, repair broken keys, do necessary case cabinet repairs, check electronics for excess noise, re-solder bad jack connections, check foot control functions, clean pots and controls, tune correctly and test play. Entire unit is detailed to look as close to new as practical. Any keyboard that cannot pass the above criteria after necessary, practical restoration gets salvaged for parts.


Microphones:

     We test each mic by ultimately going directly to the element. As there are many different mic connector configurations that both came stock and may have been modified by users, we cannot guarantee that the mic will “out of the box” connect correctly to your input. Most can easily be modified either by the end user or if requested by us (a nominal fee will apply). Each mic is cleaned and polished and it’s sound quality / operation condition noted.


Test Gear:

     Test equipment is a varied department so the tests / repairs we do to one is probably not applicable to another. Each is cleaned inside and out to a practical amount. Each is tested for function, calibration and accuracy. Tube testers have their internal tubes checked, electrolytic caps checked / replaced, tube sockets cleaned, controls cleaned and knobs tightened. O-scopes are checked for basic function. Power supplies are checked for correct output and regulation where applicable.

Electric Clocks:

    
Each clock is disassembled and thoroughly cleaned inside and out. Mechanism is lubricated and checked for loose or non-working parts. Motors are checked for freedom of movement and condition of windings, brushes and bearings. AC cords are replaced and a fuse is sometimes added where space will permit. Faces and hands are cleaned as well as the inside of the dial crystal (glass). Finish touch-up are sometimes made. Entire unit is detailed to look as close to new as practical. Clocks are then re-assembled and checked over a 48 hour period for accuracy. They are then bagged to await packing for shipment.
 

 Due to limited resources we are only able to do restorations / repairs on OUR OWN inventory and unable to take OUTSIDE / CUSTOMER repairs.
If you need work done to your gear,  TRY         SOME         OF         THESE         RESOURCES


WARNING: PLEASE USE CAUTION WITH ANY ELECTRICAL DEVICE. ANY REPAIR AND / OR

RESTORATION SHOULD BE UNDERTAKEN ONLY BY A QUALIFIED TECHNICIAN. THE TEXT'S BELOW

ARE NOT INSTRUCTIONS FOR DOING YOUR OWN REPAIR AND ARE NOT COMPREHENSIVE IN SCOPE.



*Amplifiers are measured with .775 v, 1kHz Sine wave with amp at clip into a dummy load.
Amplifiers are each measured independently of each other.

 

LINKS TO OUR 'HI-FI' DEPARTMENTS

Amps and
Pre-Amps

Receivers

Cassette
Decks

Tuners

Turntables

8-Track Decks

CD Players

Reel-Reel
Decks

EQs and Signal
Processors

Speakers

Betamax and
VHS VCRs

Turntable Cartridges

Tube Audio

Ne'cessories

Speaker Parts

Record Players

Vintage Radios

Vintage
Walkmans

Headphones

Stereo Parts


Wondering where the "tone" you remember went?....

Vintage  Stereo Equipment receivers speakers Classic Silver Audio Collection and jerry gahagan

 

.... Surround yourself with Silver and find it again!

 



 
RESTORATION PROCEDURES    |  REPAIR RESOURCES  |  LINKS  


POLICIES, SPECIFICATIONS, AVAILABILITY, INFORMATION
AND PRICING SUBJECT TO CHANGE  AT ANYTIME  AND
WITHOUT PRIOR
NOTICE
and changes may not be posted to web immediately
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Due to limited resources we are only able to do restorations / repairs on OUR OWN inventory and unable to take OUTSIDE / CUSTOMER repairs.

If you need work done to your gear,  TRY         SOME         OF         THESE         RESOURCES


_____________________________________________________________________________________________________