Analog synth Korg with problem.

[toneless]

Ok. I've got an analog Korg with 6 presets. Four of them work perfectly but two of them are lost.

I can barely hear the oscillator at the background and at high volumes.

Strange is that, waiting for a minute or two and playing a note it sounds as normal but the volume quickly fades out after a second.
Do you have something to suggest?
Bad cap I suppose?

[Transmogrifox]

for one, it would be good to know which Korg analog synth it is.  It would really help if you can get your hands on a schematic as well.  If your not familiar with the guts of a particular synth, it can be very hard to debug these things without a schematic.

Yes it could be a cap...or maybe just dirty pots.  maybe a bad digital chip?  (presets digitally controlled? or are you just referring to knobs and sliders?).

You may also want to introduce yourself to one of the DIY synth forums, since those guys are nuts about synths and have likely experience problems such as this many times over.  Us stompbox guys are nuts about stompboxes.  I can honestly say I have not had the cover off my Korg yet, though I did spent a fair deal of time studying the schematic so I understand how it works.

All the same, I'm sure there are a number of people who frequent this forum that also play with sythesizers.  If you go to "sticky" and read the thread about "What to do if it doesn't work" you will get a lot of good info about a format for posting that will help us help you better.

Regards--

[toneless]

I'm mentioning at the "subject" that it is an "analog" synth. No digital chips...

Anyway, I'm closer to the problem now. Thansk

[Paul Perry (Frostwave)]

Well, even if the oscillators and filters are analog, the keyboard scanning mechanism is certainly digital! Odds are, it's a polysix, with a leaking battery! plenty of those out there..