Seems like its Korg week this week, this time it’s an SQ-10 analog sequencer that needed new power supply capacitors. The SQ-10 is obviously styled after the ms-10/ms-20 and shares the same form factor. It makes a great companion to these or any other Korg hertz machines.
Another re-capping job, this time it’s the Korg 900ps. This machine is preset based with a few modifiers. Accessing the power supply board was a little tricky and involved having to remove the rocket switch assembly, once removed access to the board was relatively simple. Not a bad machine at all and quite a rare piece.
On the workbench this time is a Korg Trident. It needed new power supply capacitors and a complete calibration and tuning. The machine itself could be considered to be three synths in one. There’s a synth section with sixteen oscilators, a brass section and a string section. Since it’s all analog, tuning the machine is quite a long winded task. But ultimately worth it since it has a nice rich sound and character.
Here’s our Korg MonoPoly, it was in need of a general service. I replaced the power supply capacitors, fixed a problem with some scratchy potentiometers and gave it a full tune and calibration. The MonoPoly has a great sound and is often overlooked, if you see one for sale it’s definately worth a look (or should that be listen).
On the workbench this time is the rather rare Jen SX-2000, this little analog monosynth was originally intended to sit on top of an organ. Because of this the controls have been placed in front of the keyboard rather than the traditional placement of behind. This odd little machine has a diode filter and I was pleasntly suprised at how this unit sounded once I worked on it. The keyboard needed repairing, some screws were missing and of course it was completely out of tune. A little bit of work and this fine little gem sings again how it should.
On the workbench this time is a Roland TR-808. The maracas weren’t sounding too healthy and the snare sounded a little strange. I suspected the noise generator was at fault since this drives both voices. After inspection and some work my suspisions were correct. Now the maracas sound great again and the snare sounds considerably fatter than before the surgery. All in all this 808 now sounds as phat as it should.
Boom-Tish-Boom-Tish!
This time on the workbench is a Korg MS-50, this is the expander module for the Korg MS-20. This unit had a dead oscillator, after repairing it I noticed the jacks were very scratchy and cleaned them as good as possible, many of them may well need to be replaced in the future but for now it’s working fine. All that remains to do is to recap the power supply and calibrate it back to factory defaults.
On the workbench at the moment is an Elby Designs ASM Wizard. This is a DIY semi-modular based around the ASM2 synth. To say it’s big is an understatement. The machine is currently not working 100% and the synth board has been checked out by Elby Designs themselves. So the only thing that could be wrong with it is the wiring loom. I’ve already corrected a few errors in the wiring but more remain. As you can see from rear picture, this is quite a job to troubleshoot.