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Since 1982.



This page is dedicated to one of the 'coolest', and most successfully designed, vintage units ever made. The EV / Tapco 100M, Entertainer Powered PA Mixer w/ built-in 2x 100 Watt power amps, Spring Reverb, and dual Graphic EQ's and also featuring a full access, patch bay. It really 'tics all the boxes' for the heart of a 'small-medium' sized group PA system. I've used one for years starting in the late 1990's and have owned at least one ever since. It was recently time to go through my primary one to do some general maintenance so in doing so I learned quite a lot about it, and did not see much in the way of substantive information about it's technical aspects on the web. There is a very basic service manual for the EV / Tapco 100M Entertainer out there, but does not list much in the way of Voltages, Test Points, Biasing, DC offset adjustment or anything. This page will not strive to be 'all inclusive', but will present any useful information we glean in the process of refurbishing our units. At this point, any parts numbers / references, etc do not indicated that we have any of them for sale, but simply posting as 'reference' material.





(Unrelated photo to be replaced)

Construction started 2/7/2022:

     I have owned and used a Tapco 100M Entertainer powered mixer for decades, starting in the early 90's, which was about a decade after it was introduced. My Orion Blue book shows them ranging from 1982 thru 1991, but one of mine has an internal date of 1981 (although that could still support a 'marketed date' of 1982 as the internal date is when it was manufactured, although typically units will start being made available earlier, not later). I have see a couple references on the web stating either 1981 or "late '70's" as a starting time period. Regardless, they started somewhere in that time period (if I find out more accurately I will post that info), and were originally designed and marketed by "Tapco" which was a company founded by Greg Mackie (of "Mackie" electronics).

     Tapco built some rugged, affordable units. Many garage bands in the late 1970's and early 80's used the original TAPCO mixers, ie; 6000 series "6000", "6001", "6002" etc (remember having to use a pair of pliers or Vise Grips to turn the controls if the garage was too cold? I do!!!) They also had a dual, graphic EQ, model 2200 and a stand alone, Analog / Spring Reverb, model 4400A (I had both of those at different times too). My more recently acquired Tapco 100M is internally dated 1986.

     These are great powered mixers for small to medium sized groups / gigs, or for singles / duos that need more inputs for sequenced keyboards, or multi-media inputs, or for rehershal / garage band or for using any of it's aspects separately or in combination with other units / gear. Separately it's two 100 Watt power amps, Two 8-Band graphic EQ's and a 10 Channel Mixer for expanding another mixer. Use the built-in power amps to power another system. Use other, larger power amps with the mixer. Use the EQ to simply eq one acoustic guitar. The combinations can be endless. They're in a very durable package, and quite portable.
I use mine with Bose 800, Bose 802 and Bose 901 Series 1 and / or Series 2 speakers, but they originally were designed to come with a great pair of EV 100S, blow-molded plastic enclosed speakers that sounded and performed great (and were also in a very durable, blow-molded, plastic case).

     I recently decided to do some long overdue maintenance on my main, 1981 model as ever since I purchased it second-hand, the meters have had an issue. They were cyclically 'pulsing' thru the first 2-3 segments about 3 times per second, and I wanted to see if I could address that. They still performed their main function, but the 'pulsing' was distracting. I also knew it needed some pots / controls cleaned, had one of the faders that had a mechanical issue when moved all the way down and just an overall check out / cleaning as well. My second one also had dirty / noisy controls, a couple faders that had 'mechanical' issues, and it's RCA / Tape input jacks were broken away from their moorings.

Tapco 100M Entertainer Powered Mixer ser #...0011.

     Disassembly is fairly straightforward, but re-assembly can be tricky, only because of the 'speed nuts' that don't always stay attached or in-place on the plastic case.
Before work was started on it's cleaning (pots / faders etc), I wanted to attempt to address the 'pulsing' meter issue. I got acquainted with the power supply board. It divides power out for the Mixer section, the 48V phantom power and the meters. The meters are supposed to be supplied with +18VDC, but the power supply board was only producing ~7.4 Volts. I substituted / swapped the power supply output from the other #...093 unit's power supply to the mixer of #...0011 and the meters worked. I also inverted the test, and the meters of #.0093 didn't work on the power supply of #...0011.
I had the proper input voltage to the circuit of 25'ish Volts coming into that section of both units, but on #...0011 only had the 7.4V coming out. After testing the voltage regulator and associated resistors, I couldn't find any issues. Then using my Huntron Tracker, and measuring the associated zener diode of both units, found substantial differences in the traces. Based on that I ordered the proper 1N4746, 18 Volt, Zener diodes and looked at those on the tracker compared to the 'good' one from #...0093 and they matched. Installing that diode allowed the proper 18 Volts (actually about 18.4V) to the meters, which cured the 'pulsing meters' issue. Yea!!! Finally, after about 20 years of watching that when ever I used that mixer. I also went ahead and changed that diode on the other mixer, which brought it's meter Voltage up from ~17.4 Volts to ~18.4 Volts. It's meters functioned properly either way.

     Both mixers had a couple of their linear faders that were 'loose' or had a lot of play and / or were cutting out when pulled all the way to the bottom. Upon inspection, I discovered that they 'at issue' faders had taken a blow to their knobs, which pushed them back into the mixer, which simply pushed their backing plates out of their retention clips. I simply moved the fader sleds up their path, splayed out the metal retaining fingers, pushed the plates back into place, and re-bent the fingers back down against the backing plates. Problems solved on both mixers. (they're built with Alps brand faders btw.).

I also cleaned all the pots / faders / controls on both mixers.

     As long as I was doing all of the above, I re-capped both power supply boards, and the amp / driver boards and fully tested the large filter caps (both for ESR and a full gamete of tests with a Heathkit IT-11. I also (post) tested all the caps I removed and they all tested as new!!! Yes, really. I also tested all the mixer electrolytic capacitors in the mixer section in circuit with our Creative Electronics ESR meter.

Tapco 100M Entertainer Powered Mixer ser #...0093.

#...0093 also had the RCA / TAPE inputs broken away from their moorings. I feared that they were in a plastic housing that had disintegrated. Fortunately they had both simply become broken away at their solder joints and only required a 're-flow'


- 10 Input Channels, with 1-8 featuring Transformerless, Balanced XLR Mic inputs and 1/4" Hi-Imp inputs and full compliment of controls. Channels 9 & 10 were for Hi-Level / Line-In sources such as Tape Decks, Keyboards, Drum Machines or other mixers etc.
- Dual 100 Watt power amplifiers (150 Peak Watts) that could be assigned for L & R Stereo output or for running 'Mains' from one and 'monitors' from the other.
- Dual 8-Band, Graphic EQ's that defaulted to L & R, but could be assigned to "Mains" and "Monitors" or via the very versatile patch bay, to any individual channel
- Built-In Spring Reverb with Foot Switch defeat and Peak Limited
- Pre-Gain control on channels 1-8 with 'Clip Indicators'
- Channels 1-8 feature both 'Pre' and 'Post' fade AUX's (Monitors and Effects)
- Full Patch Bay allows complete access, both In and Out to Mixer, EQ's, and Power Amps which means that any aspect of it is completely assignable or usable separately
- Built-in, 48V Phantom power for channels 1-8 (not individually assignable)
- Fluorescent, Dual Bar graph meters
- Full size / length, 2-Spring, Reverb tank (not the shortie that you see in most modern gear with spring reverb)
- Max Power output circuit (prevents amp clipping)


Power Output: 100 Wpc @ 1kHz
THD (Amps): < 0.02% @ 100 Watts / 1k
THD (Mixer): < 0.02% @ +4 dBu
Channel EQ
: Low
15-18dB @ 100Hz, Mid 12dB @ 3kHz, High 15-18dB @ 10kHz,
: -100dB below full amp output (all faders down)
Output Impedance of Power Amps
: 4 Ohm min

Dimensions &
Weight (Tape Deck): 20" W x 19"D x 8" H & 36 lbs
More specifications listed in the EV / Tapco 100M Entertainer Owners / users manuals / pdfs which are available on the web as free downloads


These are things that make the unit still usable 40 years after it's inception (I venture to state that the VAST MAJORITY of gear built today and in the past dozen+++ years will not be able to be used very far into the future and certainly not have their lifespan measure in decades due to anemic SMD parts / build /  design prevalent in most, modern chinese / CHEAP gear)

- Real 'Metal' housed potentiometers
- Pots with Metal shafts
- Shaft nuts securing EVERY potentiometer (means that every time you manipulate a control, you're not flexing the solder joints / circuit boards. Most mfg's of 'musician quality' gear stopped this in the mid 1990's_
- NO SMD components. Circuit boards are populated with normal, FULL SIZE components that most technicians are still willing and able to work on
- Metal cased, TO-3 Mosfet output transistors (no CHIP output)
- Patch bay bolted to sheet metal and not directly soldered to main circuit boards
- All I/O jacks (except for the RCA's which is why they broke on one of mine) are fastened to the sheet metal housing with shaft nuts
- Not really a part of it's original design parameters, but no "black legged" transistors (at least not in either of mine)
- Huge, Full-Wave bridge rectifier
- Huge, 12,000uF / 75W filter capacitors

- Separate circuit boards enable easier service
- Multi-pin connectors on circuit boards enable easier service
All potentiometers have access ports for cleaning
- Any channel strip can be independently removed for exchange / servicing

I also tested the transformer secondary Voltages of both power transformers. Results coming soon.


(Unrelated photo to be replaced)                                                                                                                       (Unrelated photo to be replaced)

(Unrelated photo to be replaced)                                                                                                                       (Unrelated photo to be replaced)



The information contained here is simply my personal findings and is not intended for anyone / or any entity to use to make any decisions to repair, disassemble, modify, or do anything. It is strictly for entertainment value. Please do not email any responses or call with any information related to it. It is also likely to change as new / additional information comes to light, or I change my mind or opinion. So There!




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