The flagship of the alesis line, with 88 weighted keys (Fatar) and is otherwise the same ROM Sample playback synth as the QS7 series. The 8.2 version however includes the new 24 bit DAC for a slight improvement in sound quality. I beileve all three versions have unique mother boards.
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. Also displays can fail so as to take downt he whole synth. Try unplugging the display if you get nothing and see if it boots and makes sound. If you need to access testing functions etc. press 00 and 0 while powering up. If you need a reset save your data and press 0 and 3 while powering up.
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.Always feel free to ask or check my Parts
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