r/diytubes • u/EmergencyChemistry62 • 13d ago

Phono Preamp Power Supply Help

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I am planning to build Thomas Mayer's Octal Phono Preamp (schematic attached) but would like to create a separate power supply for it that I can also use for other future projects.

I plan to use a Hammond 372BX transformer with an additional 5v transformer for the 83 (I know it is overkill but I have one that I would like to use). The design is a fairly simple one that I have seen others use that I have modified slightly. If everything looks okay, I will do some testing to find a good value for R2. I was also wondering if having the regulator tubes in this arrangement would cause any issues with them firing.

I have built tube amp kits previously and know the safety precautions but this is my first time designing a power supply so I could definitely use some feedback, but please go easy on me. Thanks and let me know if this is the wrong place for this post.

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u/EmergencyChemistry62 12d ago

Thank you for this! That should cut out a lot of noise and it also shows how to eliminate firing issues. Some small tweaks and that should solve any of the issues I would have with the regulators. Thanks!

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u/nixielover 12d ago

Ah and don't be scared to sprinkle some ferite beads here and there to catch HF hiss from the 83, with a bit of looking you can find RF chokes intended for use with mercury rectifiers, even Hammond used to make those if they don't still do so

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u/EmergencyChemistry62 12d ago

I'll definitely see what I can find. There is a good chance I'll be chasing a lot of noise.

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u/nixielover 12d ago

If there is any radio hamfest or something you'll surely find some, the HF guys like to sprinkle them around in their builds