I bought a 1952 soviet copy of the Western Electronic 639a.

[Dziugas]

Hey everyone. My name is Dziugas and I am a musician from Lithuania. A few years ago I started getting into recording, and as a means of saving money I started finding good local deals for old, usually soviet mics, re-soldering and using them in my trashy studio. Yesterday, I bought a what seems to be a soviet Western Electronic 639a copy built in 1952. As I briefly recorded the three different modes, only the ribbon mode was working, but it was rather flat sounding with loads of air coming in. The cardiod and dynamic modes were buzzing as I was touching the mic body. As I haven't done a deeper dive inside the wiring and the ribbon yet, I am wondering if some sort of a preamp would be necessary for this mic, or would the +48 phantom power straight from my interface be enough? I've read that it was usually used with a 30 ohm preamp. Please note I am a diy beginner at electronics and am keen on reading/learning, so any literature suggestions would be much appreciated.
UPDATE: opened up the the ribbon and found that it was wavy bent/loose, didn't seem like broken. Would it work in full potential if I tghtended it up (not too much of course) or should I try to re-ribbon it? and if I try to re-ribbon it, should I look for 1.8/2.0 micron aluminum foil?

 

[alphasnk]

Don't apply the phantom power on your ribbon otherwise it will destroy it Turn your preamp to max that's how it goes with ribbons! If you want more gain you can try various models of mic boosters, an inexpensive one would be the Klark teknik, which you would power with 48v!

Here's a link to aluminium foil: Ribbon Mic Aluminum Foil – Bumblebee Pro

Welcome to the board Dziugas

 

[Dziugas]

Thank you so much for your reply and for the links alphasnk!

 

[alphasnk]

My pleasure

 

[Lee_M]

Hi, welcome to the forum

I've read that it was usually used with a 30 ohm preamp.

Quite a lot of the old ribbon mics have a fairly low impedance output (compared to modern mics), I'd expect things to be similar with the Soviet ribbons from that era.

If it has got a 30Ω or 50Ω output, you could probably get a bit more signal out of it by using a 1:2 step up transformer between the mic and the preamp. That'll bring the mic's output impedance up to something closer to the output impedance of a modern mic.

Alternatively, some preamps have a "low-z" mic input option, which would be ideal for a ribbon mic like this.