Roland R-8 patchbay mod

[atomat149]

I've been using my R-8 for awhile now and am extremely driven to find some way to create some new sounds. I came across the R-8 patchbay mod (https://www.circuitbenders.co.uk/newsarchive/rolandR8.html)
and would appreciate any information on how to work this mod or at least some pointing in the right direction. I have the Jazz Brush, Electronic, Mallet, and Power Drum ROM cards and am looking for the Dance or Ethnic cards.
I've done a fair amount of electronic modding and rebuilding, so I just need any suggestions about the patchbay implementation.
Thanx

[Circuitbenders]

Find the ROM chip and short the pins together. Off the top of my head i can't remember which chip it is or if theres one of two of them, but all the pins will be connected directly to the sound card socket so its easy to identify it. If theres two you only need to mess with one.
I usually avoid the +5v power pins, but just wire any of the other pins that give you good results to the sockets of a patchbay.

[atomat149]

Thanks CrustPaul!
I'll try it this weekend. Is a a good idea to get a replacement ROM chip in case of screw-up?

[Circuitbenders]

You won't be able to get a replacement ROM chip as they don't exist, unless you desoldered the one or two in there, read the contents with a EPROM reader and burnt a new one on a blank EPROM.
Just don't short ground and the positive power rail together and you should be ok. If it isn't a custom Roland chip you might be able to find a datasheet that will tell you the pinout.