Thanks Alan & JohnK, I appreciate the additional info.

With the added info I feeling a little better. (Alan, FWIW, a few drinks puts me at my stated max, one more and I'm either crashed, or doing something I'll regret that doesn't involve using a receiver.) It definitely good to know to stop at 0db.

John, I've wanted an excuse to buy an SPL, so this is interesting. But I don't follow your (implied) equation. Once I have a measurement, how do I equate a db level to how close I am to the receiver's max output?