I wouldn't mind getting my hands on a dual diaphragm version of that capsule if they're ever sold privately for DIY.
Does that mesh around the capsule act as a Faraday cage? First time I'm seeing something like that inside of a large diaphragm condenser.
The headbasket area is a bit too tall IMO, but other than that I really love the look, especially now that I know it's not another crappy SDC electret like the crap all over AliExpress and eBay. I've definitely thought off designing my own bodies and using either wood or plastic to prototype, obviously with a metal grille, then maybe conductive tape inside to help shield it. Though these mics are doing almost exactly what I had planned (I would just shorten the headbasket quite a bit). I have no idea what specific capsule it is, but it's very much like what I was considering for my own design (I probably would've gone with a good Chinese edge terminated capsule to keep costs down). Can't wait for a multipattern version. One of the few indie mics I'm actually excited for.
Thanks for the nice comments everybody!
The top area is that height because we designed the ribbon version first and wanted to use the same body/screens for both that and the condenser. Over the years, we've found that this specific ribbon size, shape, and tuning is our favorite sound. It's the same ribbon from the RCA 44 so it's a bit longer- hence the longer top section.
Originally, we used acrylic and wood for prototyping the screens. The material doesn't seem to change the pickup significantly. The wood looked very cool but it's not too durable if you're swapping screens. I've been making new screen designs on one of those cheapo laser cutters. It's a lot of fun experimenting with different shapes and hearing how it changes the sound.
Back when we originally designed the body and screens, me and my good friend, Peter, were going to a makerspace a few times a week to machine parts. The funny thing is that the main reason the mic ended up flat is because the makerspace didn't have a CNC lathe, they only had a CNC Mill. So I figured, well, how can I make a 2x7x1 piece of aluminum both sound and look good.
The toughest part about making a multipattern version at this point is finding a nice switch that fits and isn't noisy, as well as dealing with RF from the wires. Our capsules have metalized mylar on both sides so it wouldn't be too hard to experiment with. Just need to make a capsule with nicely matched sides. If you're interested, DM me and I can play around with a multipattern one for you.
@Icantthinkofaname
The capsule is a modified version of the Debenham, Robinson, and Stebbings capsule. We've made a few mechanical changes to it. I wish I had more information about the magazine and authors, but the backplate design was published in an article written in a magazine many years ago. (1960s, 1970s?). It's never been used in a commercial product as far as I know. It's a really unique capsule. I haven't heard a capsule before with this kind of low end and top end combination. We spent a long time listening to different tensions/capacitances until we found this one and fell in love. We felt like it was different enough from the capsules we love but stood next to them in their own way. We call it the 'Debby' for short.
Yes! The circuit is a modified 84 circuit. We've changed the transformer ratio as well as the caps to allow for more of the natural bass from the capsule to pickup. In the original 84, they limited the bass since it would overload the smaller capsule. And yeah! We are lucky that we have a ton of NOS Cinemag transformers from the 90s that we love the sound of. They should last us a long time! Transformer winding is a mystic art I've always wanted to explore.
Happy to answer any other questions about the mic and the design process.
