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Hello,

I don't have any experience with synths made before the mid 1980s. I've studied many guitar stompboxes from the 1970s, however. And I've studied and repaired (to a limited extent) tone modules from the late 1980s on to the early 2000s.

The big difference between the eras is the ICs on the boards. Everything from the mid 80's on is microprocessor-based. Modern stuff is made by pick'n'place robots and 1970s equipment was hand assembled and soldered. The components were a lot bigger and could be repaired easier. The technology for populating and manufacturing the circuit board itself is much more advanced today than it was thirty years ago.

But the boards of today are almost impossible to repair. Even if you knew what the custom chips were and what the programs inside the microprocessors were, you would need expensive special equipment to get the chip off the board without damage to the board, and to put a replacement chip onto the board. Assuming that you could find a replacement chip. So even though the circuit boards are better made today, they are considered disposable and are replaced as a unit instead of tracking down and repairing an individual component.

Guitar stomp boxes are easier to compare. The new ones have cheap phone jacks and really cheap foot switches. Gone are the fat round metal heavy stomp switches of the 70s. Now they would often cost more than the effect. There is a tendency to either stay with 1970s electronic designs (the expensive boutique effects) or to go to digital signal processors. The entire popular Digitech X-series of guitar effects have -exactly- the same circuit board inside the box. There's a big complicated DSP processor, some analog surface-mount signal conditioning components and that's it. All the different effects (phaser, chorus, distortion, delay, etc...) are done by changing the program inside the DSP processor.

Modern tone modules are more likely to have the manufacturer go backrupt or be sold to a non-supportive conglomerate than for the circuitry to go bad. That is what happened to E-Mu. Plus they throw a lot of advanced circuitry into a rack-mount box and then slap on a really cheap user interface such as a row of buttons and a character LCD. In the case of EMu all their 1990s tone modules came with a very-cheap encoder knob that literally broke off the unit if the unit were to drop on the knob, even a few inches. It's impossible to get a replacement because the company that bought EMu outsourced the repair service. The new repair service doesn't sell replacement parts and charges $80 just to receive a tone module for possible repair. The actual repair charge is on top of the $80 base charge. And you pay shipping both ways. They feel it is a reasonable fee since the tone module originally cost about $1000+ ten years ago, even though they sell for $80-$120 now on eBay. This is an example where modern synths are more poorly made than the ARPs and MiniMoogs (which can always be repaired if you know how they work and know where to get the equivalent replacement parts).

I always cringe when someone writes on the web about the 'magical' sound properties of some late 60s guitar effect. Inside the magical Jimi Hendrix distortion is, uh, a few resistors, capacitors, and cheap (for the time, impossible to find now) transistors. Maybe about a few dollars of components. Yet they sell for $1000 or more on eBay to collectors and purists who must have that original 1969 Hendrix FuzzFace or UniVibe. I'm amazed that these devices aren't counterfeited. Perfect copies made from the components dug out of late 1960s TVs and Hi-Fi's found in dumpsters behind retirement homes and sold as originals. If the economy keeps sinking, I may be inclined to do it myself. Hopefully not, as I would prefer to continue to try to convince people that there isn't really that much difference between an $850 LoveTone phaser and a $8.50 Rocktek Malaysian clone phaser on Ebay.

Anyway, it's an interesting subject and I do ramble on. Thanks again for the message.

--- On Thu, 5/7/09, Mu wrote:

From: Mu
Subject: [vintagesynthrepair] Re: A report on simple repairs for your amusement
To: vintagesynthrepair@yahoogroups.com
Date: Thursday, May 7, 2009, 5:22 AM

Great post, much appreciated.

Of course I vehemently disagree with the statement below. In fact, I think you're joking.

Cheers,

Mu

> Lots of simple things. Synths, tone modules, and guitar effects are made a lot better now than they were in the 1970s.
>

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Vintage Synth Repair

Re: [vintagesynthrepair] Re: A report on simple repairs for your amusement

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