The only problem with using GPO with BiaB is the mod wheel. GPO interprets the mod wheel level as a volume control, not as modulation (effectively vibrato).

GPO does this because it's a controller that's available on many keyboards, so it makes it easy to control that aspect.

Only BiaB doesn't know that GPO uses the modulation controller differently. At the beginning of playback, BiaB (sensibly) sets the mod control wheel to zero. And if you use the humanize playback option, BiaB will send mod wheel events to the track to add vibrato to instruments if appropriate.

Unfortunately, it's not appropriate with GPO.

On some instruments (such as the piano), it has no effect. On others (such as the flute or strings) setting the mod wheel to zero set the volume of the instrument to zero.

There's no setting in GPO to ignore mod wheel events, and no setting in BiaB to not send mod wheel events at the start of the track. (You can tell it not to send mod wheel events as part of the humanize playback).

To get around this, you can manually insert CC events at the beginning of the tracks to set the mod wheel yourself. It's a bit of a pain, but it works. I can't recall if you need to do this each time you regenerate the MIDI track, though.

That's one of the reasons I create the tracks in BiaB and export them to a DAW. The main problem with that approach is that you can't import back into BiaB after you've fiddled with stuff. That's probably why using RB is suggested.

-- David Cuny
My virtual singer development blog

Vocal control, you say. Never heard of it. Is that some kind of ProTools thing?