New , Trouble from the start

[smilch]

Ok looking for a little guidance . Just finished building this and i have just about no sound. I have a sig generator at the input and I have a good amplified signal at the first gain stage . It seems like as soon as the signal hits the next stage Its gone . I know the preamp tubes and the phase inverter tube are good as I put them in a working amp and it sounds fine . As a test I removed the wire from the 470k resistor after the volume pot and by-passed the whole tone stack and injected the signal from the first 12ax7 into pin one of the phase inverter and I still have no difference . Is this a valid test ? I don't have a way to test the KT66 with a spare . DC voltages look ok .

Any suggestions ?

[Firestorm]

You wouldn't put the signal into pin 1 of the PI. Did you mean pin 2?

[M Fowler]

Start from output and work towards input, try 6L6's or 6v6 to make sure KT66's not the problem.

[TUBEDUDE]

 I have a sig generator at the input and I have a good amplified signal at the first gain stage . It seems like as soon as the signal hits the next stage Its gone . 



What are you measuring the signal with...scope? Voltmeter?

[VacuumVoodoo]

Do you have correct, or any at all, DC potential at every anode and cathode? That's always first thing to check.

[surfsup]

Measure the signal at the two pots that control volume into second stage from each input stage? Are you sure those pots are wired in correctly?

At pin3 of V2 do you have any DC voltage? What is it?

[Structo]

Yep, check your voltages.

You limited the current at start up, right?