Rakarrak's audio to midi conversion does work for some kinds of guitar
playing. I never tested it using a bass, it likely will become harder to
use it the lower the string sound its, this already was an issue for old
MIDI pickups. I don't know the quality of modern MIDI pickups, but I
guess it's better you get such a pickup. Without a MIDI pickup the
conversion only does work monophonic.
As for the synth available for Linux, assumed there should be no xruns
at usable latencies, the sound of an onboard audio device unlikely will
be good enough for usage in a band, but the available synth might
satisfy your needs assumed you're using a high quality sound card.
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