DrummerLeo
Sponsor: Unique Melody
Try the Psvane ACME 300B, that's a great pair of 300B tubes. To my ears, ACME 300Bs have a very open and precious sound, the combo of HA300 + ACME sounds like a mixture of high-end SS and 300B. I have tried TA300B, Elrog 300B, FullMusic 300B/Q, and ACME 300B recently on HA300, I'm confident enough to say ACME is so far the best tie with TA300B but in different flavors. I tested with TC, Susvara, D8000pro and Utopia+Dana all these headphones are handled extremely well under this combo.The slightly tepid reports probably originated from me. I shouldn't have said that as a brand rep. but the audiophile blood inside me somehow sold me out.
I think the Abyss AB-1266 + HA-300 is more a synergy issue between 300B power tube and the house sound of 1266, and the latest Phi TC just put things slightly more difficult then the previous version. To me, the glorious part of 300B power tube is intimating mid-range, outstanding microdynamic, extremely rich harmonic and holographic presentation. The headphone implementation of 300B placed these beautiful tonal characteristic in full-scale dynamic and FR extension context, something uneasy to obtain from speaker application. Unfortunately, I still find the 300B lacking if you are after rumbling bass and wide soundstage in a magnificent presentation.
But I haven't heard the EML 300B (I assume you have the XLS version) which is said to be the strongest 300B tube, maybe this can contribute to the synergy issue and help HA-300 and Aybss Phi TC matching. So maybe keeping the Sylvania Baldwin 6SN7GTB as-is, AB compare the stock 300B vs EML 300L with your Abyss Phi TC will clarify my hopothesis.
Susvara: The overall sound becomes fuller and richer, the treble extension is further improved, the soundstage is about 30% larger than before. IMO, Susvara still fits this system the best.
TC: Previously, I do find the 300B amps generally make TC sound a bit too gentle, even with those TOTL 300B tubes (except Elrog). ACME is like a more refined or smoother version of Elrog (which sounds very clean but a little harsh in treble sometimes, an atypical 300B sound I would say). ACME is rich and warm in the bottom-end but clean and open in the treble. Thus, I feel ACME fixes some problems of TC without affecting the sound signature of TC by too much, the extra warmth in the mid-bass makes TC sound more "approachable". However, the bass attack is still not as satisfying as it with SS amps like headtrip.
