Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: markmalin on March 05, 2021, 12:00:57 pm
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Hi all,
I'm building a stand alone push-pull power amp in an enclosure. Here are the specs:
- solid state rectifier
- one input, one output
- 2 6L6's (push pull)
- phase inverter tube
With the enclosure I bought, I'm wondering if this is going to be too small. Would transformers and tubes be too close together and cause noise? Before I start cutting into it, please have a look at the pictures I mocked up. I don't have all the tubes, so I stuck a couple "place holders" where I was thinking of putting the 6L6's, and a 12AX7 box where I thought I'd put the phase inverter.
- is there a better way to lay this out to keep noise down?
- is there a better positioning for the tubes (i.e. location of the tubes vs transformers) to keep it less noisy?
It may not be a problem, I just don't know. I'm going to be running a preamp into it. I've done this before with a small single ended 6V6 and it worked well, but I'm not sure what the cleanest and quietest layout would be for this?
Humbly,
Mark
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Look a 100 watts O.T. for one 6L6?
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2 6L6's (push pull)- phase inverter tube
one 6L6?
That is tight, any chance the PI can "hide down under"?
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2 6L6's (push pull)- phase inverter tube
one 6L6?
That is tight, any chance the PI can "hide down under"?
Actually yes. I hadn't thought of that. There's going to be very little under there other than filter caps and the rectifier.
Would you suggest the power tubes near the OT, then?
Also, OT -> PT orientation, does that look correct?
Thanks
Mark
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Also, OT -> PT orientation, does that look correct?
IMO, yes.
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heat is about all you have to worry about with the PA tubes, so
forward so air can flow behind them
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heat is about all you have to worry about with the PA tubes, so forward so air can flow behind them
I just realized my comment about the "power tubes being near the OT" may not have been very clear. My bad ;). Regarding leaving space (putting the power tubes toward the front with space between them and the transformers) being best for air flow, that makes sense. Thanks.
So it looks like I need to have the 6L6's as far forward as I can, and the transformers as far back as possible. Is it best to have the Power Tubes on the left side, in front of the output transformer, then, as apposed to on the right side in front of the power transformer? That's what makes the most sense to me.