I calibrated my sub to 73-75db on the SPL meter with c weighting and slow response with the internal pink noise of my receiver. The peaks hit 75 db, while the lows hit 73. I found this to be a good place on the physical dial on the sub.
Now, when I watch movies, i put my receiver at +5db on the sub. when i listen to music, I put it back to 0. Its all a matter of personal taste. There is nothing wrong, like others have said, to run your sub at +5db more than the rest of your speakers.
Watching Underworld the other, there were things buzzing that I have never heard in the room, I pinpointed it as the grill on my left surround...it was a little loose for some reason. Not coming off, but it WAS vibrating. Sheesh!
I also noticed some vibrations from the sub itself, from the back of the EP500, I had no idea where to look for it, anyone have any suggestions? I really didn't feel like hauling the sub out from the wall now that I have the spikes on...
