I want to say that it's a CR2032, but I can't recall for sure. I replaced mine about 4 years ago, and I have a hard time remembering yesterday. One thing I do remember is that the battery is soldered in place. The actual battery has tabs (pins) that solder into place on the circuit board. I bought a battery holder so that next time the battery is replaced no soldering will be necessary. It was a tight fit for the holder though. I think there was an IC in the way making the holder sit a little crooked instead of flush with the circuit board. It worked out fine though.
I also spent a fair amount of time looking for Matrix 6 schematics online, but the file I found only indicated "lithium battery" .... and no model number. Grrr...
I guess the only way to know for sure is to have a look under the hood.
Good luck,
Andrew
-----Original Message-----
From: zog2zog2003 <sandersp1@...>
To: oberheim@yahoogroups.com
Sent: Mon, 15 Sep 2008 7:38 pm
Subject: [oberheim] What kind of battery is in a Matrix 6 - CR2032