Question How can I use a loop to trigger harmony on a VoiceLive 3 Answer As of firmware version 1.1.01 build 161:  The only way to do this would be to physically plug one of the guitar outputs into the aux input and set the aux as your harmony source. You will need a mono 1/4" to stereo 1/8" cable to do this.
  1. Create a loop and save it.
  2. Choose your desired preset.
  3. In your guitar or vocal menu, go to the ButtonMap page and change one of the switches to "Loop Trigger" and assign the loop you wish to use. Keep in mind, to be able to trigger this you will need to be in the layer that corresponds to the ButtonMapping you did. To avoid guess work, you can assign the same switch to the same loop in both Vocal and Guitar ButtonMap pages.
Now all you need to do is trigger the loop using the assigned switch. Please note, you will want to turn down the aux output levels in your mix menus.