audio-talk

Oh, don't worry Simon, I wasn't.

Yes, Ed, that was my memory as well, but for whatever reason (long day) we did move on quickyly, I suspect Dave may have assumed that was because we didn't like it.

More likely, we had less to complain about it, so got bored

Which bit are you flummoxed about Ed? Looks to me as if all the switches are off, you indeed have just a 1M grid resistor. I can't convince myself if the (I assume feedback) network between the cathode and the grid would be affected by not having either the 47k loading, or the first stage anode load...

Again FWIW (:-)), I did comment after the event (can't remember who too), that your c3g got a bit ignored, and I thought that was a shame, as it sounded very good. As did the 6em7 and the ecl82, but somehow the smaller amps got more attention, maybe partly because of the fact they were so little, an...

there were more comments about the shortcomings of the 2A3

Not from me, FWIW.

The RC network is exactly that, a zobel network to reduce the self noise of the regulator. The resistor feeding the VR sets the current in the VR tube. (+ the grid current from the pentode). 12K sould give a total current through the VR of (about) 16ma, and 15k about 13ma. Both are ok, 0a2's are nor...

All good stuff Steve

so if i replaced the 820uf with a 22uf would that be OK (or should i just try it ?)

Guess

It might be better reducing the 2.2uf at the front instead of adding the resistor.

Does the incoming L+N go to anything other than the transformer primary? Is there anything else thats connected to the chasse? I would guess it means there is a wiring fault somewhere, but just what is the problem of course. You could try disconnecting the link to the star earth, and with the amp on...

I thought you mentioned 70v on the cathodes before, thats when I said it was in pentode area.

BTW, I had brainfade before, the cathode resistor will help things. Sorry about that.

Isn't having that cathode resistor going to defeat the point? The voltage will vary as the current through that varies. You could reduce it to 83 ohm if you took the grid to 0v, removing the 2M to B+. Or if you used a 9v battery to reverse bias the grid, you could loose the cathode resistor altogeth...

Well Nick, i have to confess that i still can't see why it should be in parallel. For AC use, the B+ and Gnd line can be considered as the same, they are connected via the low reactance of the power supply, so the anode has its load resistor and the following grid leak connected to it, and as B+ an...

Ahh, interesting play. Having a sacrificial pair of speakers to hand.

Just to show how dim I am, whats Internet Messenger? Is it your email client?