Also the Nobsound NS-01P has a nonstandard rectifier and socket, a 6z4 and Shunguang tube. I wanted to upgrade this also (maybe unnecessarily), apparently the difference between a 6z4 and a 6x4 is just pinout, and so I found a 6x4 (top) to 6z4 (bottom) adaptor from China also, ordered that and a vintage 1958 Tung-Sol 6x4. Both are on their way, but I just found out from Douk Audio that the power circuit is fixed-biased, not self-biased.
It probably sounds like I know what I'm talking about by this point, but I assure you I don't. I'm kind of groping around, and here's where I need help. From reading around, my understanding is that if it were self-biased I could just pop in the adapter and replacement, but since it's fixed biased it kind of depends on the tube, or something, and I have to figure that out.
Am I wasting my time on the rectifier? I should say I have the Nobsound plugged into an Adcom A/C enhancer anyway.
If I'm not wasting my time (and anyway the bits are on their way so I may as well use them), what do I need to be concerned about? Any advice?