For the blissfully unaware:
In SS, linear power supplies: upgrading rectifiers and regulators often makes some of the most audible and dramatic improvement in presentation. The same applies to tube components (AND: tube rectifiers), BECAUSE (in every gain stage): what the signal does is modulate the power supply's DC, via whatever active gain device the designer has chosen, into a stronger signal, until it ultimately reaches your speakers and ears.
iow: You're listening to your power supply!
again:
From those that I've spoken to, component designers/manufacturers are well aware, whatever active gain devices* they choose to incorporate in their components: the quality of presentation will be directly proportionate to the quality of the DC *they modulate, as controlled by the signal they're presented.
Note the number of times, "power supply upgrades" and, "HEXFREDs" are mentioned, in the following upgrades/paths/offers. Bybee Rails are another power supply upgrade/tweak, btw.
http://www.rogueaudio.com/The_Magnum_Series.htm
https://www.jolida.com/upgrades/upgrading-your-equipment
Odyssey used to offer HEXFREDs (ultra fast/ soft recovery) as an upgrade, but: now, just as a standard parts.
https://odysseyaudio.com/candela-vacuum-tube-line-preamplifier/.
and from Cary:
If you have not had it done to your favorite Cary Audio piece, the Hexfred option makes an awesome difference! Hexfreds are high speed low noise rectifiers and replace your existing standard rectifiers in the power supply. You will notice more speed, air, detail, imaging and tighter bass, yet a cleaner clearer sound quality. The Hexfreds help to provide a cleaner, faster DC voltage which shows up very noticeably in the sound quality. There is one more layer of hash and hardness (noise) that is removed so that you can just enjoy the music! Bass is faster with more details and the midrange and highs are cleaner and clearer. You will hear more detail with less bite.
