Circuit Overview:
The first enhancement of the Quadrasynth in a more compact package. Same VLSI ROMpler machine with less emphasis on user control and more on sounds quantity/quality. 6.1 enhancement has twice the memory (16M). The 2002 6.2 version has the new 24 bit DAC for improved sound quality. I beileve all three versions have unique mother boards. At least the 6.2 does.
Service Tips:
Always verify power supply voltages if problem looks like it could remotely be power supply related. I have seen some bad solder problems and one intermittent processor reset problem that required a new board in an Alesis product.
Parts:
Advanced Musical Electronics has a lot of parts for Alesis stuff. THey only deal with techs though.
I've also seen All electronics carry displays occasionally at low prices.