High end sound

Hmm yeah I agree it could be high frequency hearing loss because to be honest, even though I do agree Caps go on Amps, Bryston sound signature is on the sharp bright side of neutral. I do not believe its Speaker height because you have the Magnepans and if you have out 3 feet from the wall as you stated, positioning does not seem to be the issue for the dull sound you are experiencing. Cables could make a difference but cannot be responsible for your system sounding dull of a sudden. Now the combo of a Bryston solid state with a tube preamp I am familiar with and have swapped out the tubes to the point of tedium when I used the combo that was similar to yours. Great fun. It just so happens my Former BAT preamp utilized the very same tubes and I do know the tubes make a huge difference in the overall sound signature. Have you recently changed the tubes or have you been using the same tubes for a prolonged period of time? Have you gone up to the speaker and listened for any strange kind of Whiney sounds/creaking sounds (ie microphoney)? It would be interesting to hear what tube brand you are using and how many tubes the preamp requires.

Ditch the Maggies. Get a pair of Philharmonic BMR HT towers. Set them up properly and thank me later. The only speakers that compete with their distortion levels are big dollar Magicos, Rockports and the like. 

If you insist on staying with Maggies, perhaps give the .7 a try. I had both the 1.7i and the .7s. The latter were considerably more dynamic in the mid bass and had superior coherency. I could never get to where the individual drivers sounded as one whole with the 1.7is. 

As long as the gauge is thick enough for the run, nothing will sound better than plain old OFC. Fact. Anyone here who says differently is willfully ignorant or lying.

As long as the gauge is thick enough for the run, nothing will sound better than plain old OFC. Fact. Anyone here who says differently is willfully ignorant or lying.

While I agree that plain, decent gauge OFC is all that’s ever necessary, I do know of audiophiles who are genuinely convinced they hear improvements from esoteric designs. As Neil deGrasse Tyson might say, it’s their “personal truth”, as opposed to an “objective truth.” This doesn’t imply their ignorance is consciously willful or some manner of cognitive dissonance. Rather, they are highly susceptible to placebo and expectation bias. I have a local audiophile buddy who falls into this camp. I used to judge his type negatively. But it’s pointless to do so, because his proclivity to relying on subjective input doesn’t hurt anyone. If he was a conspiracy theory nut, and trying to convince others of outlandish falsehoods or getting people to join a cult, that’d be a different matter.