After reading the forum for months and building two subs of my own I still don't totally understand volume controls for subs. Seems to me that a lot of others are in the same boat based on all of the conflicting information. Can we clear all of this up? I think we should divide it into two cases 1) Subs with Plate amps Exactly how to set things up is gray area to me. Cranking the plate amp just doesn't work. I could never get down to a useful level. If I set the trim on the receiver two low the sub never turns on. 2) subs with Pro amps Most people say crank the amp and control the level with the trim level on your receiver. What is the right way to set-up a sub in each case and why? What exactly is the difference between volume and gain controls, and how do the work when used together (receiver + plate or pro amp)?