Discussion about the Korg PolySix synthesizer

Hi all,

I'm pretty much a lurker here because I never had a polysix (and still don't, and would like one!), but I did just acquire a Poly61 with issues for $25.

Of course, the keyboard worked very poorly AND the NiCd was slightly leaking (classic problems, I gather).  I snipped out the NiCd, recycled it, and cleaned up the PCB with DeOxit.  There wasn't much corrosion and the unit works fine.  I just wanted to get the corrosive electrolyte(?) off the board to avoid future issues.

But I digress.  I'm posting because the way I repaired the keyboard was to remove the key PCB from the Poly61 and replace it with the key PCB(s) from a Korg DW-6000 that I sacrificed a year ago.  The difference between the key PCB from the two units is small:  
1. the DW6k has two PCB's joined by ribbon cable, the p61 is a single PCB
2. the DW6k PCB has a carbon shorting pad underneath the rubber domes, where the p61 PCB used gold plate.

This last difference, I think, is the reason why the p61 have such keyboard troubles.  I think the metal shorting pad passivates and is a smooth surface, so over time, the carbon on the rubber dome makes a less and less conductive connection.  The DW6k's carbon is rough and maybe doesn't passivate, so it should be a more reliable connection over time.  At least, I've never heard of the DW6k's keys having triggering trouble, but on the p61, it's a classic problem.

Note that the DW8k doesn't have the same type of keyboard - it shares the keyboard with the DSS-1, if not others.  So if you do this, you have to find a DW6k.

In sum, I think my p61's keyboard should be more robust over time now that I've Frankensteined in the PCB from the DW6k.  If I do run into unreliable performance, I'll definitely post back here.

Thanks!


PS  what happened to the rest of my DW6k?  Part of it is here:

http://www.flickr.com/photos/37595587@N00/sets/72157616967698662/