SEQUENTIAL CIRCUITS

PRO ONE

This synth is one that I have always wanted. being a fan of Yazoo I always loved the crisp electronic sound of this powerful mono synth. I saw one on eBay that needed a bit of work. The tuning was all over the place and one key was broken, but it seemed functionally ok.

I replaced the DAC chip and all the electrolytic capacitors. I then did a tune up. Some of the pots were scratchy so a quick blast of switch cleaner and they were much better. One of the wooden side panels was damaged so I just rounded off the broken corner. A bit of a sand down and some wood stain and they looked proper job. I got some new knob caps to spruce up the front panel. They was a cigarette burn near the bend wheel but hey it's a bit rock'n'roll.

Once I had the synth working, I decided to upgrade it to the rather excellent Turbo CPU. This replaces the current CPU with an upgraded PCB. This allows MIDI and other functions.

 

PCB out for a service

pcb

 

Old CPU and DAC

 

Here's the new turbo CPU and MIDI board, with IN/OUT

cpu

 

MIDI install

midi

midi install

 

replaced tantalum capacitors in power supply

tant

e;

 

refurbished wood side panels

p

 

Ubiquitous Mandala shot