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”
While we’re working from home due to the virus and have all of the synths and all our recording gear in the same place, we took the opportunity to make this video about the restoration of two Prophet 10s we’ve restored recently. One of them proved to be one of the most arduous restorations we’ve ever done due to massive damage to its microprocessor system. It was a long road to get it working, but when it was done, we celebrated by MIDI chaining the two of them (which we had also both retrofitted with MIDI) and making some fantastic and massive PROPHET 20 sounds! Check out this video for a recap of the restoration process and some demos of the synths’ powerful sound.
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.
This Prophet 600 was brought in for a Gligli P600FW upgrade, which is a CPU/firmware upgrade using a Teensy ++ microcontroller board. It offers improved resolution for all parameters (128 values instead of like, 15 or 7!), a new LFO just for vibrato, arpeggiator MIDI sync and more, which you can read about here. The firmware is generously offered for free by the developer and in order to install it, we procure a Teensy 2++ board, do some modification to the Teensy, flash the firmware onto via USB, and install it in the Prophet 600 in place of the original Z80 CPU. We can do this mod for only about $100 including parts. Continue reading “Sequential Circuits Prophet 600 – Gligli Upgrade”
One of my main pieces of advice to anyone learning to fix vintage synths is to never underestimate the likelihood that whatever problem your synth has is just because of cold solder joints. Continue reading “Juno 60 (#4)”
This is a really good one. SIEL was an Italian company that always quite clearly had their own way of doing things. It is a 6-voice DCO polysynth with the ability to make just beautiful, delicate, lush tones. The square wave can go so low that it just sounds like a lawn mower in the distance. That’s not a very useful feature, but for some reason it always delights me when I encounter it. Continue reading “SIEL DK-600”
Here’s another article I wrote for Reverb.com, devised as a sort of year-end-list for 2017, profiling my favorite vintage polysynths I’ve worked on that can still be had for under $1000. This one’s for all of you who feel like you can’t afford to own a cool vintage synth. Some of these can be found for as little as $300!
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.