Secondhand Synths (Part 2)
Part two of our natter with a couple of blokes who fix old keyboards every day. Common problems need common solutions
David Etheridge concludes his chat with repair chaps David Croft and Ron Lebar of the Synthesiser Centre. Is it sensible to make mods? he asks. The men say when.
What makes do you specialise in for repairs?
David: "We do it straight across the board, really. We're the exclusive warranty service for Akai, Ensoniq, Sequential, and we do exclusive servicing on the Emulator and the E-max. So we're familiar with them all. With all those makes they have differing faults, which is a good sign. If they were coming in with one persistent fault that would not be so good."
Ron: "The problem with numbers of repairs is that, obviously the more popular the instrument, the more often we see them. It doesn't mean that they're more unreliable, but just that there's more of them about. Also they're more highly stressed when used professionally and therefore more likely to go wrong — not that professionals abuse their equipment, they just use it more and that greater usage promotes greater tendency to failure."
As a result of your experience with earlier generation equipment, do you tend to try to modify it in the light of experience?
Ron: "As a rule, yes. On earlier equipment we do the mods off our own back and charge for them. There would be no feedback to the factory on that because they would no longer be in production. The information is of no value to the manufacturers."
David: "Servicing seems to have changed. People take notice of what we say if a particular piece of equipment needs a certain mod, or if we find something that keeps going wrong. Then they tend to come to us to ask us what we think is necessary. Or we'll suggest something, and that will alleviate problems that have been occurring."
Ron: "One problem that we're in an ideal position to deal with is the question of voltages. In America their equipment operates on 60 cycles per second, here it's 50, and that can confuse computer equipment. The computer will think that there's a problem with the power supply and try to shut itself down to protect memory. Again, in Europe, all their equipment is designed to run on 220 volts and our 240 volts tends to stress it more highly, causing more heat and strain in the mains transformer. There are a number of things we can do to solve these problems, and we have the experience of our customers to draw on, so we have an advantage over the manufacturers in suggesting ways in which we can improve the instrument. We have tried in the past, and still do, to make sure that any modifications that we adopt have been tried on several instruments, and extensively tested, before we suggest it to the manufacturers."
"I wouldn't recommend putting MIDI on any monophonic synth, because nearly all monophonic synths of the non-computer variety have CVs and gates, and there are a number of CV/gate to MIDI converters on the market. Whether they're built in or not, the price would be about the same, and it would be a bit pointless going to all that trouble and then tying it to one instrument. Or it could be put into a box and then be available for different instruments as you changed them. You wouldn't want to build one into an ARP Odyssey when if you put it into a box you could also use it on a Minimoog. If the instrument fails it can be replaced with something else in a MIDI setup.
The pseudo-polyphonic string and brass synths, like the Omni and the Crumar Multiman based on organ technology, would be far too costly to convert to MIDI because they don't have control voltages or computer systems from which MIDI information can be deduced. A mod like that would cost about as much as a Mirage on which you could sample the original sounds anyway.
It is worthwhile MIDI-ing an acoustic piano of note, say a CP70 or 80. There are kits on the market, albeit high priced, to do just that. A CS80 is a first generation polyphonic keyboard. It is possible to modify as the keyboard information is encoded and it's straightforward to read from the digital system on CS80's to get the information you require for MIDI. In addition, it's got a great touch sensitive keyboard, ideal for a master-keyboard."
Getting technical info for your vintage keyboard is a lot easier now than it was even a few years ago. Ron and David had horror stories of both RMI and ARP being incredibly loath to supply data for their instruments, as though terrified that either anything could go wrong, or that anyone not versed in the mystic arts of their own supposedly secret technology would presume to want to attack the works inside with the tools of the trade.
Moog's reputation suffered in this country over the unserviceability of the Minimoog (in their defence, they later gave away full schematics with each Memorymoog) and the early Sequential policy was not to give out any details to anyone who wasn't a registered service centre. One upshot of this was the number of dodgy modifications done to early analogue synths which made them less reliable. Over the years Ron has had to undo many such jobs. As well as adding facilities and interfaces to instruments he's a past master of the MIDI update.
"MIDI updates work well, in general. They have to be computer based, or they won't work at all. If you're buying a second hand instrument, watch for any modifications of a non-MIDI type such as keyboard interfaces to allow two instruments to be coupled together, different audio facilities, attempts at altering the filtering, multiple outputs, etc. Some of these types of mods are very unreliable — either badly designed or badly executed. SSC: (Contact Details)
Feature by David Etheridge
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