Jumping In With Both Feet. DIY Ribbon Planning.

So, I've watched several videos of DIY builds for ribbon mics.
I've got a donor body that I want to work with. It's not a ribbon body, but a cheap cheap condenser.
Seems like the hardest bit will be building the motor frame.
I've got the donor en route, a pack of 2.4" ND magnets, just ordered some 1.8 micron foil, and a corrugating tool.
I'm mostly gathering the materials, hoping to have all the components within a month. I read the RCA 44 used a 4.7mm wide ribbon, and about 2.4" long, that was 1.8 microns. I'm going to aim for 3/16" wide, which is close.

I haven't made up my mind on a transformer. Edcor is tempting, but Geistnote has an in house unit that is affordable, and supposedly sounds close to the RMX1.
I know people seem to like Lundahl, but that's a little more than I am looking to spend, unless it really is worth it.

Any thoughts on transformers?
A lot of folks checked out the thread, but no replies. Lol. Guess I'm gonna have to take a bunch of pics as this project comes along.

I decided on a FAB 1:38 "Metron" trans. I watched a video where a guy used a FAB XL to update an older RCA "paintbrush." The mic model name escapes me. Sounded nice though. Price was pretty agreeable, data sheet included so that should take out extra measurements and guesswork.

The magnets have been delivered, though not picked up. The donor body should be here by the end of the week. The ribbon foul and tool is on the way, and I ordered the trans last night.

Need to get material for the motor frame, and copper tape.

I know it might not be exciting to everyone, and this thread will definitely need pics... but I'm pretty stoked.
Hey! Only a couple of people plus you and I have checked this post.
The rest of the 'views' are crawlers/bots.

I don't have any transformer advice but I'm always interested in a DIY project! Looking forward to seeing how it goes. :)
Lol. I've been doing a LOT of reading and video watching the last couple weeks. Deciding on the trans was the last major bit. It'll be a couple weeks before I can start in earnest, but by that point, I'll have all the materials together.

Hey, one other enthusiastic member ain't bad.
Alright. Picked up the pieces that came in. The magnets are thinner than expected, but are pretty strong, so shouldn't be an issue. Thinking I might double up. Don't know if that will cause any issues, but I don't think it will. I nabbed a BM800 for the donor shell... and it is the cheapest thing I've ever seen. Lol. Good thing I just want the outsides. The data sheet is something else. Lol.


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rob aylestone

Well-known member
I saw the topic, but didn't read it because I didn't realise it was about building a ribbon mic. I saw ribbon planning, and didn't know what planning would be involving ribbons. Now after reading I've realised you're building a ribbon. Sorry I didn't make the link. It's an interesting project - but I'm not sure enough of us have experience on actually building mics. I've never ever done it. I have mended quite a few, so the process wouldn't worry me - but transformers? To me they are just components, and I wouldn't know anything about brands. I know one 'brand' SOWTER - they have made transformers in England for ever, but Americans prefer their brands. Now of course we have Chinese unbranded ones. I guess you need to try swapping them to see? It's kind of a hobby in itself. Keep us updated.
Well I didn't want to call it a build yet, since I'm mostly gathering components, and was seeking ideas. Like I said though, I've watched and read a bit on DIY builds, and looked up some general specs, and jumped. I have enough magnets to do two mics. I should end up with enough foil for more than that. Using the cheap BM800 as a donor body is strictly
cosmetics. If it works like I hope, I want to try and make something classic looking, which will take a lot more elbow grease to come up with. I also kind of want to use mild steel for the ribbon motor frame like Royer does to beef up the magnetic field. Lots of guys make them with plastic, and I may do that round one. There's a fair bit of enthusiasm, a familiarity with hand tools, and little actual technical knowledge... but there's probably worse things than mimicking the specs for models and sounds you like.


Well-known member
Back to what Rob stated, you are moving into an area I know nothing about, but I am keeping an eye on the topic. Mics are so much a dark art.
Attempt at a basic template for the motor frame.
Will see if it translates over into something usable in the near future.


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Ribbon foil, crimping tool are in my mailbox. Transformer is in hand. Copper tape en route. Got the Austin DIY pdf, and I've found the information in there worth the $10 asking price.
I'm likely to gut the donor body on lunch today.
Crimper/corrugating tool, foil, copper tape, and epoxy in hand.
Moved at the end of last month, so I haven't set up a work space. Need to get the acrylic or whatever material to construct the motor cage.
I found a little e book and YouTube series for this sort of thing. It even has a parts list and what not. $10 purchase. Now, I've been super lazy and haven't gotten around to piecing anything together, but I've got all the bits but the motor frame. I need to source the acrylic pieces for that. Life got in the way. Lol.