Hello everyone..
I just finished building my heywhat 504.. but no sound at all.. no hum.. no hiss.

I found 340v at pin 1 and 6 of the preamo tubes that I guess that is too much..
after the diodes bridge the voltage is about 450v, then go trough the 100ohm/5w resistor..
i used a 22uf and a 32uf instead of the 32+16uf caps. maybe could it be the matter of the high voltage problem?

anyway, I checked the voltage before turn on it.. the others seems to be ok, I found the 450v at the HT of the output central.. and about 450/500v (dont' remember exactly) at the el34 pin 3.

Nothing burned when I turned on... so I think that the problem could be a discontinuity in the preamp.
How could I verify it ? thanks
Paolo