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use an empty cocacola can.. it'll do the job

bassdriver wrote:I have a AKG D 12 mic that is fucked.

Is it sounding thin or does it have no output whatsoever? I repaired a D19 the other day and the D12 has a similar modular capsule. Often the voice-coil corrodes or breaks.

A lot of CB mic bodies will sound crap, but there may be a few that are useable. You need to judge by look and consider internal reflections, etc.

You could find a Ronette body like the one I used here (damp any suspension springs used though):





Doug, if you have much luck then I could maybe spare you some better foil than the leaf variety.

Rodabod wrote:

bassdriver wrote:I have a AKG D 12 mic that is fucked.

Is it sounding thin or does it have no output whatsoever? I repaired a D19 the other day and the D12 has a similar modular capsule. Often the voice-coil corrodes or breaks.

thin close to dead. I resoldered all the cables but that didn't help. as I have a D12 and a D25 in great condition I never really bothered to get this one repaired. I bought it on the flea market for 5 $. there's been a guy from austria on ebay selling NOS capsules for those mics for 320 $ ..... a bit steep as you would say.

otisroom wrote:You want to sell that D12? Can't you get it fixed? that's a very nice mic.

well I would feel strange to sell a not working mic. but for a project like making your own ribbon mic I would give it away.

I also have a Grosstuchel for you Funkberater.

pm me if you're interested.

Junk stores, flea markets, and garage sales, are great for this. There are lots of those crappy "elvis" mics out there, as well as p.a. carbon mic bodies.

Rodabod wrote:

bassdriver wrote:I have a AKG D 12 mic that is fucked.

Is it sounding thin or does it have no output whatsoever? I repaired a D19 the other day and the D12 has a similar modular capsule. Often the voice-coil corrodes or breaks.

A lot of CB mic bodies will sound crap, but there may be a few that are useable. You need to judge by look and consider internal reflections, etc.

You could find a Ronette body like the one I used here (damp any suspension springs used though):

Doug, if you have much luck then I could maybe spare you some better foil than the leaf variety.

Oh I remember seeing this somewhere's. Here or over at prodigy maybe.

This is nice. Well done!

Can I ask a few questions?

Do you have any closeups of your motor?

How thick is the ribbon?

How long is the ribbon?

How wide is the ribbon?

Whats the gap between the ribbon edge and magnets?

I'm using a ribbon that's 1/4 inch wide. That's what the plans call for anyways. But the ribbon in my 74b is narrower than that I think.

otisroom wrote:Do you have any closeups of your motor?
How thick is the ribbon?
How long is the ribbon?
How wide is the ribbon?
Whats the gap between the ribbon edge and magnets?

I have close-ups, but they are not very interesting as I don't plan to remove the mesh blast protection.

It's 2.5 micron. About 1" long. I'd guess around 3-4mm wide.

The gap is minimal. Definitely less than 0.5mm. You need to minimise the gap without rubbing in order to give good output and to maintain bass response. This is relative to ribbon width, so it's easier with wider ribbons.

The motor in my one was stolen from a Beyer Headset mic. It now has a Sowter transformer, but I don't particularly like it. It's too bright which is due to the motor design.

Here's my first ribbon motor frame. it's kind of rough around the edges. I made it on my porch with a jewlers saw by hand.





The magnets are 3 inches long and the ribbon will be 1/4 inch wide. She's a big girl.

Looks good. Have you insulated each of the ribbon clamps from each other?

Rodabod wrote:Looks good. Have you insulated each of the ribbon clamps from each other?

No. I have not done that yet. I've been trying to figure that out. Do they both have to be insulated from the frame and magnets? Or can I just float/insulate one clamp?

You may have guessed that I've been following the "Austin" DIY Ribbon mic plan. But since his frame is made of plastic there's no need for any instructions on insulating the clamps.