Just remembered that I asked a sales person once about using a Roland guitar synth with my bass pickup, and he said "it won't work". He couldn't give any more details, and he hasn't been all that knowledgable (is that a word?

) before, so I'd take that with a grain of salt. The Yamaha G50 MIDI converter has a Guitar/Bass switch, so I think there is a difference in how the MIDI conversion is done. My guess is that it primarily has to do with the sampling/frequency detection, the algorithms are probably optimized for different note ranges. If that is the case you may find that the MIDI interfacing works, but not too well...