This article will use Kontakt to illustrate how to setup a multi-output virtual instrument in order to have 1-to-1 control and relationships between song tracks and mixer channels.
In the example below there are six tracks and six instrument outputs. Each Track Inspector "Channel" field is assigned to a subsequent output in the mixer. That gives direct control over every output from the track faders. In the example below you can see that track 3 is assigned to Kontakt output 3.
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If you're producing music using Kontakt or any similar multi-timbral and multi-output instrument, this is the best way to approach setting it up for the most convenient workflow in Studio One.