Sounds like it's more of an issue with the speakers and the recordings!
Could be. But the VSX-918V-K (rated slightly higher, at 120wpc, than this -915) hits 1.0% distortion (not 0.1%) into 8 ohms at
36.7 watts. Now I know all amps are the same, and all that, but come on, if the amp is making 1% distortion at 36 watts (like its big brother) then you can't assume the amp is capable of good sound. Given his issue is bass notes, I'd think a does of clean power would help provide those peaks he is missing as his amp goes into progressively greater distortion as he demands more bass.
As Peter says, a new AVR would be the more practical approach.
