Focal Kanta 2 and CODA 16 amp

@mclinnguy , thanks for your input.  The floor is covered with carpet/ padding from the front of the speakers to underneath the couch that is my listening position.  The speakers themselves actually sit on the hardwood floor.  I draped a heavy throw reserved for chilly nights over the TV that sits between the speakers and it makes a marginal positive difference.  I've done the mirror trick to find the first reflection points on the side walls and hung blankets in those areas.  Again, it resulted in a subtle rather than very obvious, positive difference.  I have no doubt the combination of more well-placed treatments would have a cumulative effect, not least of which would be me taking up residence in the garage.  My wife has limited patience with what my hobby/ obsession has done to the parlor (her daytime office), as 11 speakers, two subs and SR HFTs all over the walls are kinda obvious in the room.  One of the acoustic treatment companies had a sale and I talked about placing some acoustic panels here and there.  That conversation didn't go well.  Thus, my options for optimizing the space are limited.

My vacuum tube journey has taken me through new and NOS Mullard, Brimar, Amperex, Conn, RCA clear top, black plate, triple mica and Amperex 7316.  With my previous McIntosh amp, the 7316's were the champs.  I avoided the likes of Telefunken as I understood they were on the brighter side.  With the new amps, the triple micas are currently in use, while the pricey 7316's sit on the sidelines.  C'est la vie.

I've had a few conversations with Andy at Backert about options, and as was pointed out above, Andy agreed the experiment of decreasing the DAC's volume would be telling to diminish the effect of the Rhythm's gain.  It has, in fact, been extremely helpful, to the point where I can listen to just about anything now (emphasis on just about).  Another Backert owner who had a similar problem to mine had the factory reduce the preamp's gain and it made all the difference.  The cost to do that is very reasonable and I will likely go that route.

I'm getting even further afield here, but some months ago I decided to go all the way and replace my "good" ethernet cable with a high end one in the chain from my switch and filter to streamer.  I removed the filter yesterday and what do you know: the system sounded even better.  Horns and female vocals were tamed just a bit more.  Whether the benefits inherent in this cable (it has its own magical filter thingy on it) might have been conflicting with the other ethernet filter, or my ears and brain are starting to hear the improvement I want them to hear, it was another step in the right direction.  I've also been moving IC cables around in the system to gauge the impact.  There are no shortage of variables to play with, and there are times I consider whether different speakers could be just but the doctor ordered, but the good news is I am getting closer to better sound.  And, through it all, the home theatre sounds good, which is extremely important, as it is the bulk of my time.  Cheers,

Robert

There is definitely no shortage of effort on your part to achieve the sound you are looking for. Thanks for the thread, always good to read what other audiophiles have been doing in their journey to audio nirvana.

 I removed the filter yesterday and what do you know: the system sounded even better. 

As many have said, once one has the level of quality hifi components that you have acquired in your digital chain, everything matters. I have recently been reading on another forum about what many claim is such a huge difference with just the DC cable on the linear power supply on the modem. Crazy to believe. I don't even have a linear power supply on my modem (yet).

There are no shortage of variables to play with, 

Yup, choice is good. Here is another variable: Software

 I don't believe it was discussed previously, but at times, on certain tracks, I have found Squeeze was a little too hot, and going to Roon smoothed out some high frequency energy, similar to going from Telefunken to some "lesser" tube with less transparency and less high frequency extension. I would think Conductor is similar to Squeeze. 

Enjoy the process!

Removing the Muon filter was a good idea. 
I would also suggest to go back to all stock power cords to get a benchmark and to hear if any of your power cables negatively impact the sound. 

Hmmm, stock cords in place of my eclectic collection of name brand cords, eh?  Interesting idea.  I am fearful of what I might find, as the popular, well-reviewed cord(s) I once revered could be a dud and an impediment. Or, it could reinforce my faith, knowing that "better" cords are indeed better...

Fear not. The stock cords give you a reference point and sometimes help determine your next move. I’ve used this method more than once and it proved worthwhile in understanding what cabling the new components may need. It never convinced me that stock cords are better but it did point me in a right direction. Amplifier is the most impactful change in a system after speakers. You have worked hard to voice your setup and achieve synergy with your mcintosh. Now you need to do the same with coda. 
I went thru few amps in the last couple of years and I can tell you every amp change triggered additional changes including repositioning speakers. It’s never plug and play.