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Hoffman Amps Forum image Author Topic: Power tubes too close to power transformer  (Read 3720 times)

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Offline dscottguitars

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Power tubes too close to power transformer
« on: July 28, 2012, 10:40:29 am »
Hi, has anyone had a problem with 6L6's or any other power tubes being too close to the power transformer?  I have a chassis that puts two of them, one side of the push pull, in front of the power transformer about half an inch away.

Thanks...

Daniel

Offline triode

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Re: Power tubes too close to power transformer
« Reply #1 on: July 28, 2012, 01:07:11 pm »
Dynaco sold a ton of MK III's, no one ever complained or had problems with the tubes being that close to
the transformer : http://www.head-fi.org/t/513514/fs-2-dynaco-mark-iii-amps

Personally, I have never had a problem, other than sometimes I think it can make the transformer get
hotter than I would like. Personally, I see heat as the main problem with putting them really close. Is
it well ventilated?

Offline dscottguitars

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Re: Power tubes too close to power transformer
« Reply #2 on: July 28, 2012, 01:36:06 pm »
Hi, thanks for the reply.  Yes it is well ventilated, completely open in front and back.  I'm wasn't worried about the transformer getting hot, only the effect on the tubes if any.  Glad to know it's been done before.

Offline thelonious

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Re: Power tubes too close to power transformer
« Reply #3 on: July 28, 2012, 02:26:28 pm »
This little 2x6V6 PA amp I'm converting has about 3/8" clearance between one of the power tubes and the PT, and it has been functioning happily since the 40's, if I'm reading the date codes correctly. Other than the PT getting hot like Triode mentioned, it seems to work quite well.

Offline Tyrannocaster

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Re: Power tubes too close to power transformer
« Reply #4 on: July 29, 2012, 06:33:26 am »
Let me add to the chorus: my latest build (a tweed Pro-ish thing) has an OT that is bigger than I realized - in fact, the damn amp won't fit in the cab because the OT won't quite clear the speaker frame. I just measured the distance between the OT and the 6L6s and it's just under half an inch. The amp sounds fine - no hum at all. Anything else about its sound that I might not be crazy about I ascribe to the fact that I just prefer Marshall style sounds to tweed, LOL.

 


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