question about measuring current draw of whole amp. was i right?

[zambo]

i added a 1ohm resistor between the standby switch and first filter cap on my amp so I could measure the ma draw of the entire amp ( not including heaters). I measured .048 mv which converts directly to ma like when i bias it right? so my amp draws 48 ma roughly. Ok, its a pp 2x6v6 amp running off of a 269ex using a 400 ohm cathode R ( shared) . I get -18 volts on the cathode. its biased a little cold for a amp with 270v on the plate (252 plate to cathode voltage). OT primary Z out is 12k into an 8 ohm speaker.Still 48ma for the whole amp seems low. Did i do this right? I dont want to fry the parts on this. The amp sounds pretty good. Any idea's on this? 269ex PT and 125c OT, both are hammond transformers. would love to know if I am ok with this design. Sounds louder than a 5 watt but not louder than a 10.

[firemedic]

I think that sounds about correct, with no signal going to the power tubes. Playing it full blast, you would see that number rise.

[zambo]

I played full blast ( everything on about 7) and it didnt seem to rise. I thought it would too. Thats what made me wonder a little.

[PRR]

>  I measured .048 mv which converts directly to ma like when i bias it right? so my amp draws 48 ma roughly.

Yes.

> 400 ohm cathode R ( shared) . I get -18 volts on the cathode.

45mA plate+screen. 3mA for the little tubes. Very reasonable.

> 252 plate to cathode voltage. OT primary Z out is 12k into an 8 ohm speaker.

If 12K push-pull, a theoretical plate power drain would be 6K. And 252V/6K is 42mA.

The 45mA was plate+screens. With 6V6 the screens are about 5%, so 43mA in plates.

42mA is exactly equal to 43mA for any tube-amp purpose.

> 48ma for the whole amp seems low.

You've been looking at 2-6V6 plans with 10K and 8K loads. A 12K load does not need as much current as a lower impedance.

With this load and idle bias, the full-roar current won't change much (maybe 5% more screen current).

I don't see a thing wrong.

> Sounds louder than a 5 watt but not louder than a 10.

It's probably honestly 5 or 6 Watts, but if it sounds bigger that's fine.

[zambo]

Thats sweet! Thank you for the replies! I will post a vid clip tomorow after work if i can. I sounds pretty good but still needs some tuning. I just didnt want to play it to much and risk melting it. Again, Thank you! Greg

[zambo]

7 watt Pony Express "White Unicorn" clean tube amp with 2 6v6 in push pull

the cleans on this come out ok. the overdrive is a bit nasty.