One of the things that has been the most helpful for me over the years in sort of syncing up my general understanding of electronics theory with understanding how synthesizers are actually designed is reading circuit descriptions in service manuals. A lot of the American companies especially wrote really great, detailed explanations of how their instruments worked, and reading them has helped me to both understand the specific circuits they discussed, and understand more broadly how different objectives in synth design can be achieved… and more quickly recognize what’s going on in an unfamiliar circuit.
Because I’m a nerd I guess, I thought it might be fun to make some step-by-step “circuit descriptions” like that for synth circuits that don’t have them. My first featured circuit –the system through which the Yamaha CS-80 handles preset, panel and memory switching– is sprawling, but actually fairly simple, much like the synth that it comes from. Continue reading “How Sound Selection works in the Yamaha CS-80”
Remember when we used to do a blog post and try to think of something to say about every Juno 106 we worked on? It’s a good thing we stopped because this is the 31st Juno 106 that I (Alison) have personally restored, not to mention the ones that Darian has done.
We had a week full of Junos (Junoes?), with three Juno 60s and four Juno 106es here all at once. These are the ones I did last week in between grinding away at various aspects of an insane Minimoog Model D restoration I’m working on and building a new power supply for a Rhodes Chroma.
This RS-09 died in a basement flood and has rusty bubbles all over its panel. It has a helpful piece of masking tape labeling the notes on the keyboard with their note names. We were tasked with fixing it basically for as little money as possible, but the only thing we could have done but didn’t do was make it look nicer. Continue reading “Roland RS-09”
I bought this Juno from a guy named Mike in South Jersey, with a shaved head and a gold chain. I met up with him at his garage studio behind a roller rink, where the Juno had been used for over 25 years by musicians providing live accompaniment for the roller skaters. Now the music is performed by two “old cowboys” (his words) on two Hammond console organs. I also met Mike’s overweight English bulldog, who he introduced to me as his girlfriend. I think her name was Bethany. Continue reading “Roland Juno 106 (#7) – this is New Jersey”
This MonoPoly had the worst kind of problem when it arrived: a very intermittent problem. It had a tendency to fade out randomly, and then randomly fade back in. The first day it was here, we ran it for 12 hours continuously without any such incident. It took us a long time to figure out what was going on because it was hard to get it to replicate the problem. Continue reading “Korg MonoPoly”
I was kind of excited to work on this because it is the close relative of my own and favorite polysynth, the Kawai SX-240. The repair job started out smoothly and then descended into hell. Continue reading “Kawai SX-210”
After I finished actually working on this Juno, I finally caved in to my perverse scientific curiosity and decided to see if I could use parts from a few half-failed Juno chips (ones from various Juno 106s I’ve worked on, that weren’t fully restored by the soaking/stripping process) to create some fully-functioning ones. Continue reading “Roland Juno 106 (#6)”