Hi bachfugue1. B3X can growl very nicely. You can output B3X to T-Racks input, but understand, the B3X leslie is basically the T-Racks. You will have to bypass the B3X leslie, and output to T-Racks and output to main output. There are many discussions, and presets on my Organ tips page in this forum. Tell me what you are looking for, and I can get you close in B3X.