There are several audio-to-midi converters, both stand-alone and VST.

I think Jam Origin Midiguitar2 is free. I "ASSUME" this could be be done in real time by outputting the audio track to a midi track with this vst.

I have only had this vst for a few days and only used it to lower single notes into the bass range in real time. There is some latency. As I remember it is polyphonic.

This also would turn Matt's trumpet into a midi instrument I think. Then he also could play the riff to Smoke On The Water....lol

Billy