Kawai R100 Soundswitcher board by Drumware Inc.

Here are some photos of the ROM switcher board in my Kawai R-100 Drum machine. The expansion board is dated 1987. My unit contains three 4Mbit mask ROMs:

MN234000KAA, MN234000KAB, MN234000KAC

I think these ROMs are the original R100 and R50 and the R50e judging by what I’ve read elsewhere on the web.  The sound format is 12-bit (non-linear) with a 32kHz sample rate.

P1030550 P1030548 P1030570


This entry was posted in Kawai R100 and tagged . Bookmark the permalink.

3 Responses to Kawai R100 Soundswitcher board by Drumware Inc.

  1. grantb4 says:

    I have successfully copied the ROMs, done a little analysis on them, and designed a ROM switcher board of my own.

  2. grantb4 says:

    You can remove the chip that is in there and replace it with the one you bought. Just make sure you use proper chip removal and insertion technique. You can probably google how to change a socketed chip. Also, for more on the R100, see this link:


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.