Anyone heard of problems with Oktava MK-012 capsule connections?

[mixsit]

Tracking a band today I had to add the screw in pads for one of the overhead pairs. That led to level differences between the pair. I basically tried to trouble shoot between songs, cables and a second set of caps etc. (Tracks before the pads were clear and clean BTW.
It turned out the one mic's level was not just lower but also heavily rolled off on the top.
Afterwards, going through all the checks and swaps again it's now back to normal, balances with the other.
These pads look to be dirt simple just a resistor (although it actually looks more like a capacitor) across the center pin to shield perhaps. All these parts (cap, pads etc) use a spring 'loaded disk to the center pins apparently to make the connections.
I seem to recall once before having to reseat or tighten, but that was I believe with just the caps.
Didn't see anything in some searching but I'm wondering now if that could be sort of a known flaky part in these mics?

Tomorrow should better. ...sans pads', and a pre with less gain which was what started the mess in the first place.

Just curious too,, I know waves' aren't always symmetrical nor need to be, but these dogged' tracks peaks were all quite a bit smaller and I don't want to say 'clipped, but more uniform on the bottom side. Related I suppose?

 

[xaudia]

Oxidation can be a problem.

Try GENTLY cleaning the central pins with some very fine emery paper, followed by some isopropyl alcohol on a q-tip.
Make sure your hands are clean before you start and just gently clean the pin - keep the emery and alcohol away from the other bits!

Stewart

 

[moresound]

By your description - you don't own a Chinese knock off pair of the MK-012s - so that's good.

 

[mixsit]

Nope, from Warren (pre- Zen IIRC but.. nope.
I doubt oxidation- I guess it could happen but they're clean in there. I wonder more about that very light bit of pressure the disks push on the pin. It isn't much pressure at all. Or, question, what is on the back side that seat disk? A very light wire I suppose?

 

[xaudia]

If I recall right the capsule pin connects by pushing through and against two thick gold plated wires, one either side, like a pair of lips. They could also become oxidised or bent, but i would recommend to start with cleaning the capsule pin as it is easy and does not involve dismantling the mic. However clean the studio, it still has oxygen and humidity!

 

[sjjohnston]

(although it actually looks more like a capacitor)

From what you describe, it sounds like one of them is acting like capacitor too.

I suppose it's possible that whoever was assembling the pad in Russia stuck a capacitor in where a resistor belongs as a result of inadvertance or an odd sense of humor.

As for the connector, it should be exactly what you've described: a fixed pin (on the downstream side of the capsule and the pad) and a little tiny spring-loaded circular plate with a dimple in the middle (on the upstream side of the pad and the mic body). No wires anywhere, at least not on ones I've seen. It's unlikely that's the problem: more likely a loose connection inside.

 

[xaudia]

I may be thinking of the Neumann km74, which has the two wires!

 

[mixsit]

..As for the connector, it should be exactly what you've described: a fixed pin (on the downstream side of the capsule and the pad) and a little tiny spring-loaded circular plate with a dimple in the middle (on the upstream side of the pad and the mic body). No wires anywhere, at least not on ones I've seen. It's unlikely that's the problem: more likely a loose connection inside. ..

I definitely have some trouble shooting to do which I haven't gotten into again yet but something occurred to today.
Ever notice taking ohm readings how unless everything, the leads and what you're 'touching, is spanking fresh clean you have to either; use quite a lot of force, or scraping' movement to get down to the real (lowest) reading? This is the way it is with very small signals (voltages etc.
This came thinking about that dinky little spring force