New development on old project: Roger Mayer RM58

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Well-known member
Dec 27, 2010
Cool to see so many people interested in this!

Yes, just about any serviceable 1:1 should do the job. You could even make the compressor unbalanced and omit the transformers--that's actually the original design. By the book, there are probably "better" choices than the UTC A-21 or A-20.

I was trying to replicate a specific example that had been modded by Roy Cicala at the Record plant.

I do think AMI will have more UTC transformer models available soon, if not already (so it might be worth an inquiry if you want something to fit the holes in my Protocase enclosure file)

The UTC iron does "a thing," and that may be why I like it in this device. It's much more audible transformer coloration than modern Lundahls or Sowters or whatever. In the RM58 (which is very much a "character piece" for me), that's a feature, not a bug.

Many surplus suppliers seem to have 2N3820 stock (I got a bunch from

I may buy some more soon, as I'm thinking about whipping up a couple more of these for personal use (they really sound great, and my business partner would never let me take the one from our mix room as he uses it on every single mix now).

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