I bought a Poly800 (Mint!) including a manual (Bonus!). Everything works perfectly, except... SysEx seems to completely scramble it's 1984 brain. I'm no stranger to MIDI, and have a few other synths in my rig, all of which work well with SysEx. Is the 800 a SysEx dud?

There is no sys-ex on the POLY-800 . It's MIDI software is very basic . It always sends on channel one , you can change it's receiving channel , and set the sequencer clock to midi - that's it . In 1984 the only MIDI synthesizers out at the time were the POLY-800 , JX-3P , EMULATOR II , JUPITER 6 , PROPHET 600 , and a few others . There was no sys-ex in 1984 .