Solving the "complex music problem"?

Thanks. I'll try the listening experiment.

I can't figure out how to reply to a specific post. But thanks all for your input.

Hi, this is the OP,

So many helpful and interesting comments here. I can't reply to everyone, but I can thank everyone. What a great community. You've definitely given me a lot to think about.

To the many people here (and elsewhere) you've given me pointers on positioning my speakers, thanks. I've moved them further from the wall, helped immediately, and I thought I was being careful about that. I've also been playing around with how much to turn them in towards the center. 

Thanks to everyone who said they've noticed the same thing and that at audio stores they always play simple music to make the rig sound best. IMHO if the music is simple enough, with a little reverb, even vary entry level systems sound terrific. It's when the music gets more complex that the better systems make the most difference.  It's always been surprising to me that there wasn't much talk about this. Nice to know I'm not imagining it. I now think that a lot of the reason people don't talk about it is that they normally place music from smaller ensembles, so it isn't that big of an issue for them.

dcoffee makes a good argument for why my theory of why the problem occurs may be wrong. I'm 3/4 convinced, but still not sure. As a Bayesian would say, you've caused me to significantly rethink my prior assumptions. 
jeffseight, on the other hand agrees with my original thinking and puts it very well. "If you consider that in symphonic music live you hear each instrument  however in a two channel stereo you hear only on instrument ,the driver, it seem obvious that the two can not compete." If any readers, say, design stereos for a living and definitively know the answer to this, I'd be very curios to hear it. 

Varidian notes that live music has this issue also. You're right. My rethinking was greatly influenced by the fantastic concert I attended last night in Ann Arbors' "acoustically perfect" Hill Aud with an excellent sound system. It was a music festival with a bunch of different groups, so I got to hear a lot of different styles. The sound was amazing. But when I listened and thought about this particular issue, I realized that the sound was "mushing all together" there, almost as much as it does at home. So, to a significant extent, that's just what happens when a whole lot of sonic vibrations share the same air. This insight has helped me lower my expectations in this regard, which helps. 

Many people say the biggest issue is the source. Totally agree. I was streaming HD music from Amazon and the complex music problem was a big issue. Then I switched to Qobuz and the improvement was immense. IMHO the single biggest difference maker in audio is the quality of the recording itself. That said, even with great recordings I've still noticed that complex music presents problems. 

Thanks again for all your thoughts!

Hi, this is the OP again,

Not sure if people are still following this. It’s been a great conversation. Here’s a happy update.

At the suggestions of many, many people, I’ve been playing around with room positioning and set up more. It has made a huge difference. Just sat here blissed out listening for the past hour. My system does sound a lot better now. I’ve also realized that a certain amount of blurring is a natural part of a lot of music, and I’d do better changing my expectations rather than trying to "fix" the "problem" so it goes away completely (although too much blurring is still a problem).

That said, this thread wasn’t really intended to be about my system. I was curious about this general phenomenon that I’ve heard on many systems. I was curious about what the best way to minimize the issue. I got a lot of great advice on that here.

Some people are curious about my system. I stream Qobuz through a NAD M10 and play that through Focal Aria 948s. When I’ve got some spending money, the weak link in my system is clearly the M10, which is an amazing piece of equipment for the money but doesn’t fully exploit the speakers’ capabilities.

I’ve tried to upload a picture of my room without luck. I’ve pasted a link to a photo below. The speakers are about 20 inches from the wall, 9 feet from each other, and 11 feet from me. I’ve got them toed in more now than before, which helps a lot.

Thanks again for all your input.

https://photos.google.com/photo/AF1QipMeoUz0OSCuchK7tqI7YCj7OrxEfmvEi6_QGhdm

Thanks ghdprentice for letting me know how to post photos. The virtual system page is just showing an error message now. but when it's working I'll post the photo.