While I agree with what you said about sub trim level, I personally have talked to more than one manufacturer, and they recommended +3.0 to -3.0 for auto on performance, and not overdriving the signal on the positive end.
While i feel overall there is no detriment, I find it most consistent to recommend a range like -3 to +3 or -5 to +5 after speaking with people about how to use their product with Audyssey. We will jsut have to disagree there, because I think when you first use Audyssey, or install a new sub, going ahead and finding the proper gain setting for that range is easiest, then you are done. Every time I run Audyssey now after a room change, I never have to pull the monster out and get behind it, it always lands around -2db , so then i can easily boost +4db.
Plus, why use a higher gain setting than you have to?
Hurting performance? No.
Good practice? I think so.
The other useful trick is you dont have to take all your measurements, just take the minimum and calculate and see where it set the sub. Adjust gain if needed, then repeat. Once you have the sub where you want it, run the full measurement scenario.
Edited by gadgtfreek - 12/27/13 at 12:48pm