Well if your ever near the capital your welcome to have a looksie. I have done 5 different PSUs, exhanged all parts every time, used all possible filament feeding I can think of. AC tied to gnd and elevated up to 95 V over gnd and DC regulated in two ways. The 350 reg I used that worked best was one I had in an ECC88 RIAA and it was silent there.
Elevated DC is a thing I havent tried but I dont think it will solve it.
Its a shame since the sound is promising. Transients is almost to much and bass region firm listening to it.
Elevated DC is a thing I havent tried but I dont think it will solve it.
Its a shame since the sound is promising. Transients is almost to much and bass region firm listening to it.
Elevated heaters is something that makes a difference on indirect heated tubes.
I run them starved to.
Thr pre is right now resting in storage while an old eico saved from a certain death in a dumpster is playing.
I hope one of my friends will give it a new home soon since it´s not even close to medium FI
.
I run them starved to.
Thr pre is right now resting in storage while an old eico saved from a certain death in a dumpster is playing.
I hope one of my friends will give it a new home soon since it´s not even close to medium FI
.What do you think about a 680R 9W/5k 2W divider? Thas what I found at a glance.
This is point where I throw it out of window.
I reset memories with vodka instead. Cheaper
That is what I use and I confirmed all harmonic noise is bellow -100dB level ref 0dBV by remeasuring one hour ago with 4 things connected on inputs and the amp wired also. The Tx and AC mains wiring is on same chassis.
You may see one power ground star on (-) of a big PSU cap, then a chassis star near the RCAs, and a common on a copper leaf hanging off a wooden rod near the signal circuits. That signal circuits return points ground connects to the near RCAs signal ground star with a cable. The PSU ground connects there with one cable. The mains earth prong connects to chassis at a point near its entry. The input runs from selector to audio circuitry and to output are 75 Ohm coax. Not the fat variety.
Ok, Ic. The black wires. But how does it relate to poweramp? Does that connect to earthground to? Then you should have a loop.
The power amp on rack now has a system grounding as in blameless amplifier Douglas Self book. There is no loop bcs what I measured for such low harmonic noise was with the amp connected.
