Ribbon Microphone
A ribbon microphone and associated tooling! Still in progress.
In 2025 I helped produce a friend’s album, and during that process was reminded of my enduring love of RCA/AEA ribbon mics (and introduced to the joy of the Coles 4038!) Shortly after, I decided to learn what I could about how they’re made: read a pile of old patents, reached out to AEA for some detail on their process, watched some videos etc. I’d struggled a lot with feeling like there was no point to making effects since digital was so effective and anything I wanted already existed, but microphones are still kind of open territory!
I landed on neodymium for the magnets, since that’s what contemporary manufacturers use and it’s more effective anyhow. Motor frame is custom, I designed it in Fusion and then 3D printed it. I also printed a little “paper crimper” to corrugate the ribbon, and picked up some amorphous toroidal cores for the transformer.
Pains in the butt
Crimping the ribbon was kind of a pain, but mostly just a learning process. Then, after installing it, I realized I’d oriented the magnets the wrong way around, so I had to remake the entire motor, lol.
Winding the transformer was the worst part though. It’s a 36:1 ratio between the two windings, so six turns of one wire against 216 turns of the other all in a little tiny 1 inchish donut. If I were building more than a couple of these I’d definitely build a toroidal winder first.
The circuit works! I’ve just been hung up on modelling a better body for it. I’ll get around to it eventually…
