As being a brand new member of the Outlaw Saloon I've had a great time looking through the various posts.

Noticing this post in particular, I'd like to interject that what you may be experiencing is not an electronics issues but might be a room acoustics issue.

Please bear with me on the dry reading until I can get to the actual "meat" of this post.

While I don't want to limit anyone from purchasing new equipment (that's the fun part right?), please consider your room acoustics as a potential caviat for your sound issues.

I'm a small A/V installer in the Midwest that has rekindled putting in HT and 2 channel A/V equipment after being out of the business for 15 years. With all the digital advancements in electronics and speakers, I noticed that sonic clarity has been achieved (not to be confused with ear pleasing sound in my opinion) with great success.

However, with great sonic clarity and multi-channel systems, general room acoustics now play a greater part in the overall sonic experience.

My point is this. What you may be experiencing is unforseen bass standing waves on the bottom end of your system (since you reference that bass is more prominent at higher volumes) or that you're actually creating overtones at high frequencies in your room that essentially make "white noise" noted as sharp displeasing sound that limit what you want to hear in your ear at higher frequencies.

I would suggest maybe some ultra critical listening to your present system to determine if the source of your listening issues stem from actual equipment or are an effect of your room creating the above sound effects. Increase the listening volume in discrete jumps and then listen to music that enhances the issue, or just use a pink noise generator (if you have one) with increasing volume to recreate the problem.

If you determine that is, in fact, an acoustics issue, there are simple things to try.

Point your subwoofer in an odd direction in your room (assuming the Earthquake Sound SuperNova MKIV12 is a 12" sub??) or to add any large floor standing vases you have in your house into your HT room (i.e. creating some hemholtz resonators to change the standing wave pattern).

For overtones, throw an additional rug on the floor or put a bunch of pillows (like 10) on your couch/recliners in the room.

Basically, anything to substantially change your room acoustics to define if it's an acoustics issue or actual equipment issue.

After you determine that, you can take more reasonable measures to combat the problem (i.e. add/change carpet, put in sound absorbant materials on the wall/ceiling, etc.)

From recent installation issues I've had, the room has essentailly had just as much to do with the actual sound quality of the HT/listening room as the equipment itself.

If you've considered this approach to your issue already, please disregard the post.

If you haven't, I hope this helps your quest.

Cheers!