Hey guys, happy to chip in the little that I know from experimenting!
This is the video where I played a live duet with Eric Marienthal on a Youtube live stream:
The time starts at 1:23:00
I was bringing him into my show live through Zoom. The first thing you have to make sure when using Zoom to make music is that you disable any audio processing on zoom. This can be done through the audio settings tab. This allows zoom to get out of the way and allow your audio equipment to pass through the system without any compression or distortion.
We were using a backing track that Eric was playing from his end. So when Eric and the backing track plays, it comes into my ears perfectly in sync. I hear it and play together with that accordingly. To the live audience watching, it sounds perfectly in sync too.
However the one downside is that MY saxophone playing, going back into Zoom and into Eric's ears, is slightly delayed. Now this delay can vary very widely. With good computer, audio equipment and very strong internet through an ethernet cable, this latency can be brought down to a minimum. Eric told me that it sounded like I was just behind the beat. So it didn't affect him that badly. Do bear in mind that he was in LA and I was in Singapore, 15 hour time difference away.
I would say if you were to make music as a duo, it is not impossible, but anymore than 2 instruments will probably be an issue.
I know many companies are trying to find a way to allow for remote live performances with zero latency. I'm not sure when that will happen, but at the moment this is probably the best method there is for now