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You can find a great explanation of this and much much more in Steve H's Ultrabeat Unleashed video:
Here's a quick run through of how to create separate aux tracks for upto 8 stereo and 8 mono voices from one ultrabeat instance:
1. In the I/O of a soft. inst track select Ultrabeat > Multi output
2. To be able to process voices individually we need to route a voice to itÊ¼s own
channel strip. Click on the Out section of the Voice Mixer (where it says Main) for
the Kick (or any voice) and select one of the outputs.
3. Do the same for the other voiceÊ¼s in the sequence, selecting different outputs.
4. Open the Mixer.
5. There is a little + button below the mute and solo buttons.
Click on the + button creates Aux tracks in the Mixer assigned to the outputs of Ultrabeat.
6. Create as many Aux Channels as you need to handle the outputs from Ultrabeat.
Let me know if you have any other questions.