First Express PP build

[mcrracer]

I have built quite a few amps this year both PP and SE. I have Built a SE DLM type Express build that worked very well. I guess I got cocky and jumped onto a PP Express on a smaller than normal chassis with EL34. I think I got some splaining to do. I am trying something different as far as chassis and enclosure. I have read and re read most of the posts on TWs. First of all The term " It's Alive" is most appropo with this amp. When power is switched on from standby it seems to be a living creature I think the EL 34s are way too much. Plus I am having some lead dress issues because it feeds back and squeels with any volume past 1 or 2. There is a level of hiss , more than any other amp I have built, even with the volume control at minimum. I got it to work enough to plug a guitar in and it sounds great, but I am thinking 6V6s would have been more than enough. A question for the Gurus...pin 1 tied to pin 8 for the EL34 will that harm a 6V6 or do I need to remove that connection? I have already tried to tame it a bit with a 12AT7 in V1 and a 5751 in V2. I still need to chain this beast down to the work bench. My camera was stolen during a Summer burglary and I haven't replaced it yet...OK, OK so I live in Chicago. I may be able to borrow one. The lead dress is passable I think and relatively well routed in the pre , PI and power section. The power supply board is a bit of a rats nest. Squeeling and howling , is this generally a pre amp lead dress isuue? Any suggestions short of throwing it in the lake will be appreciated. Thanks

[M Fowler]

Yours is a little bit confusing since your able to play through the amp but squealing and howling usually requires reversing the primary OT leads to your EL34s.

Mark

[mcrracer]

Thank for stepping in Mark, I know what you mean there I tried reversing it. That's not it I will go back in this afternoon and try moving more wires around.

[M Fowler]

I would then say the presence control is bad or circuit is not proper, disconnect the presence wire from the impedance switch and see how it sounds.

Mark