Sound quality vs. volume


Looking for a bit of expertise here:

I recently made a few changes to my setup and while overall pleased with the results, I’m on the quest for better.  I’m hoping you all can help me diagnose an issue I’m hearing.

When listening to music at lower volume levels - say less than 1/2 total volume, the clarity, imaging and dynamics come across far more coherent and “in focus”.  To use an often over-coined phrase “It’s like I’m there in the room”.  As I start to push the volume up a bit, closer to live-performance levels, the sound becomes increasingly “mushy”.  I know, a highly technical term, but the best way to describe what I am hearing.  The bottom-end loosens up - getting a bit boomy, the crispness of the mid-range and highs fade and the imaging falls out of focus.  These are all incremental with volume until I get to the point where it’s just unbearable.   

I’m no expert by any means but feel it might be room acoustics.  I already know I have a less than ideal setup with a nearly square room (21x20ft) with 60% of the surface covered with clear birch wood paneling. Some things we can’t change (easily).  I do not have any acoustic treatment, just lots of soft furniture.  What I find interesting is that my old setup (Magnepan 1.6) didn’t suffer to such a degree.  Maybe with the new setup there is more to loose?  A mystery.  

For a bit more context:  
Speakers:  Dynaudio Contour 60
Streamer: SoTM sms-200 Ultra
Amplifier: Peachtree Nova500

Within the 20x21ft. room, my speakers are 4ft. from the wall, I am seated 13ft. from the front wall (a bit back from room center). Speakers are 9ft. apart.

Any thoughts?  


wanderingmoo
Wondering if with low volume the room is not causing so much trouble, but with higher volume the room becomes more apparent. Is your room treated? This is mandatory, especially with your style of speakers.
Try sound treatments(to absorb as much as possible) behind your listening position(live end/dead end). I’ve found, in a home listening room, the opposite of a studio(ie: dead front wall), works very well(kills ,"slap echo"). With planars; diffusers on the front wall, where the most direct sound(back waves) from the panels, will hit the wall, help a lot. Also- a listening position, closer to 2/3 of the way, back from the front wall(gotta experiment, to find the best spot). The higher the SPL, the more you’ll excite/notice room modes(reinforcements/cancellations), and overload. That CAN be overcome, to a great degree, by applying the above! If all else fails to satisfy, consider DSP, to control some of the more difficult issues. Of course, the better the room’s treated, the better DSP works too.(https://www.neumann.com/homestudio/en/how-to-improve-the-room-acoustics-in-your-home-studio) (https://www.sweetwater.com/insync/lede-live-end-dead-end/) (http://www.sengpielaudio.com/calculator-roommodes.htm http://realtraps.com/modecalc.htm) (https://www.stereophile.com/reference/108tech/index.html)
Here’s a cheap version of Auralex, which works very well at controlling resonances, when applied correctly. Anyone that tells you different, is simply ignorant/inexperienced. The thickness of the foam is important, with regards to the frequencies affected. 2" is a good bet, for home audio. Don’t forget those corners, to control bass reinforcements. Hopefully; you have autonomy, with regards to room asthetics(WAF can vary, SO widely).(https://www.ebay.com/itm/12-pcs-2x12x12-IN-Premium-Acoustic-Foam-Panel-Tile-Wall-Record-Studio-Soundproof/202344013871?hash=item2f1ca4a02f:g:zc4AAOSw8SpbJrNM) and https://www.ebay.com/itm/Acoustic-Foam-Corner-Bass-Traps-2-Pack-Charcoal-12-X-24-X-12/162157685284?hash=item25c159ea24:g:JBMAAOSwZVlXokXc
Insufficient headroom at high output., room treatment will help some but will not make up for headroom deficiency
With 88dB speakers and(a rated) 800wpc(into 4 Ohms), listening 9’ from the drivers; one would have to be deaf, or- want to be deaf, to run out of, "headroom". Of course: anything’s possible.