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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

A few questions about transformer placement in an S5 K-12 tube amplifer

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Hi all, I'm working on an S5 K-12 tube amplifier kit, and I have a few questions about transformer placement in the box. My current plan is to build an enclosure with four pieces of wood cut on 45's with an aluminum plate as the top. Then I'll have the four tubes emerging from the top of the case, and the 3 transformers mounted upside down on the aluminum plate behind the PCB / tubes. As I haven't seen any cases built like this in my travels (since most decide to mount the transformers on top of the case), I wanted to make sure this was an acceptable layout. The bottom would be left open for convection cooling.

This is similar to what I want to do, except there would be no raised portion behind the tubes, only screws in the plate where the transformers are attached beneath:

An externally hosted image should be here but it was not working when we last tested it.


Thanks so much for your help!
 
Looking at the kit built here:

S5 Electronics K-12M Tube Amp

I see they have the transformers inside a metal enclosure. Based on that I don't think you will have problems but I would suggest two things. (1) rotate the opts 90 degrees with respect to the power transformer, and (2) add some small hole patterns for air to escape the top plate to allow for convection to help cool everything.
 
Ah, thanks for the lingo refresher 🙂. So, as a followup, would this type of layout work, with the only exception being the transformers and capacitors mounted upside down?

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Yes, it is bad to have them close together. in addition, Rotate them so that the output transformer cores are 90 degrees to the power transformer core!

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The closer they are to each other, the greater the magnetic coupling and the more hum the power transformer will induce into the output transformers.
 
I have just realized the main power transformer might be a bit too heavy to mount underneath the metal, is there any issue with mounting the transformers on their sides? As in, I could mount the main power transformer on the left of the case and the 2 output transformers on the right of the case, both of them on their sides rather than either right side up or upside down.
 
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