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
Let me say this about that.

Once anyone gets a very satisfying balanced system and speaker/room setup, most often you will find you very rarely listen as loudly as you used to. You are busy being immersed, involved, hearing things previously undiscovered.

Once a level of involvement is achieved, it is time to move to superior content, broaden your interests/experiences, move into phono if not there, move into Reel to Reel if not there, ... all of which enrich the experience far beyond tweaks.
It's the amp that causes 'mushiness' at higher volume levels. Upgrade your amp.Some big/heavy "high current" mono blocks.
The last three posts are correct in their own way except newtoncr 105dB is pushing the danger point for your ears. Tweek the bass and the treble up just 1-2 dB and 95 dB will sound just as good. Elliot you can have a marvelous sounding system that will not push comfortably beyond 85 db. But id you have a system that will do 95 db comfortably that is heaven for some music not all. A string quartet at that volume would sound rather ridiculous. jkbtn right on.
Unfortunately, distortion sets in way before high volumes are reached. There is distortion even at moderate levels. But the higher the volume the higher the distortion. You’re just used to it, that’s all since it’s always been there. You’re unaware of the distortion until it’s removed. It doesn’t have anything to do with amplifier distortion. It is more mysterious. Much more mysterious. it’s not really a secret because no one knows about it. 😲
Been away a few days - I pulled out my SPL meter and mushy stars right around 80db. (A-weighted) I know someone asked.  

I took your advice and plugged the ports completely and the sound improved.  Less but much tighter/cleaning up the lower few octaves.  

I also played around with poor-man sound treatments.  This also seems to help.  I put egg-crate foam behind a few paintings and prints on the back of the room.  This reduced reflection.  I was getting some “slap” from the back wall.  No doubt more can be done here.  Wondering if ceiling treatment might help?  It’s the easiest place to treat without disturbing the look of the room. I’ll keep at it.  I have a 110” projector screen between the speakers - maybe sound panels behind the screen?  

As for the Amp.  I have no doubt mono-blocks carved out of mountains of billet aluminum would yield an improvement.  I haven’t tested that theory yet.  Stay tuned...  and thank you for all the advice!