Vinyl sounds a bit thin and slightly strident.

One thing to do right away is get rid of those ARC supplied EH tubes. These are almost as horrible as the Sovtek. You will not believe how significant Telefunken, Mullard, Amperex, etc., 6922/6DJ8 tubes would make on the LS7. The midrange textures, decays and smoothness in the mids will be quite a surprise.

I owned the PH2 for many years and loved it. It may be solid state, but this is an outstanding phono stage. And it is balanced which seems kinda strange that you are driving it into the LS7 which only has single-ended inputs. Are you using adaptors to/from the PH2? If so, I highly suggest that you look to change to the PH1 which is essentially a single-ended version of the PH2. Stay away from the PH3 - it might sound "right" at first hearing but a return to the PH2 shows how natural this product is.

The Cardas Nuetral cables are great from a tonal neutrality perspective but they remove so much of the spatial aspects in the music that comes through with other cables. As colored as the Cardas Golden Cross ICs can be, one of these between the LS7 and the amp could also be a major sonic effect that you are after.

John

Dgarretson provides good input on the TX2575 resistors. I just replaced 22 resistors in the audio section of a Counterpoint SA-2 with TX2575 and the clarity was greatly improved. I can relate to all the praise that Michael Elliot gave to these resistors when he compared them back in 2007. However they had little to do with the SA-2's incredible portrayal of space which is inherent in the SA-2's overall design. And I suspect such changes here will not be as beneficial as tube rolling (in the LS7) for the improvements in bringing more life to the mids.

Until you get those EH tubes out of the LS7, all the fiddling with cables is only going to result in one set of strengths/weaknesses for another.

I can not suggest a specific 6922 tube for the LS7 because one tube type might be so incredible in one product but be outperformed by another tube in another product. I have no experience with the LS7....only the LS5. And I did not go through the multitude of tube-rolling efforts with the LS5 like I have with other products since I owned the LS5. But the Amperex quite handily outperformed the stock ARC tubes in both the LS5 and the SP-10 that I had before it. There is so much to gain from the trials and patience of trying many tubes in each component.

The Tele 6DJ8 is the king in the SA-2 but in the Aria WV preamp, the Amperex 6922 works like no other. And in the CAT amps that I use, a number of Valvo, Philips and Amperex all work incredibly well; the Telefunken was not a good fit at all here with the result being a most flat presentation. Without trying these in each product, there is just no way to know.

From a view of the circuit board on the LS7, it looks like 2 of the tubes need to be the same but the other two you could try different brands. Maybe try an Amperex 7308 for a little more detail and dynamics and the Tele or Amperex 6922 for more midrange smoothness and bloom.

Once you get a set of tubes here that take the performance to the next level, the IC from the LS7 to your amp will be CRITICAL to achieve that next level of 3D performance.