Question about MK012 capsules

[Adam P]

Hey all,

Recently I've been having trouble with one of the capsules for my Oktava MK012s. It will occasionally give off a sound as if it were outside on a really windy day (we all know how great wind sounds when picked up by a mic). I've isolated the problem to one particular capsule, since it does it on both preamp bodies, and I don't have a similar problem with the other capsule. Both are the cardioid caps that came with two unmatched MK012s from Guitar Center (I bought them last minute before a session with a friend and didn't have time to try them out, nor would I have known what to look for at that point anyway). They worked without a hitch for that session and for another one I did shortly after this past New Year's, but then this occurance showed up fairly regularly. I've noticed that it will go away (sometimes temporarily, sometimes for the duration of its use) if I tap gently on the side of the capsule. However, its just too risky to use on a serious session (it was acting up this weekend and I was forced to use a 219 as an overhead in a pinch...it got the job done but it just wasn't the same).

Any thoughts from you more experienced and/or more knowledgeable folks? Since it goes away sometimes when I tap on it, it makes me think that something is just loose, but I'm not sure. Is it something that can be fixed fairly inexpensively (probably not by me), or should I just save up $200 and buy a pair of matched hypercardiod capsules from Sound Room? I only use these for overheads at this point.

Thanks for your help.

 

[Marik]

Hmmm,

If it was a LD enclosed type (like Neumann or AKG style), the first suspect comes to mind would be humidity. With a SD single diaphragms it is... yeah, the humidity just might be trapped between diaphragm and backplate.
The first thing just try to dry it out--put into a box with silicon packet (whatever it's called) and leave for a while in a dry room, then we will see.
BTW, do you feel any changes in the sound when it works fine?

 

[Adam P]

To be honest, my ear isn't really good enough to discern any major sound differences when it is working. I just had both of them plugged in to my little 6 channel mixer about a half hour ago to test again whether the problem was in a capsule or a preamp. Listening over my headphones (7506s) my voice didn't sound terribly different between mics, but I wasn't ABing them or anything, or really listening for differences. I don't know how humidity could've affected one and not the other, since I've always kept them together, but stranger things have happened. Hell, just yesterday both headlights on my car managed to burn out at the same time right before I had to drive from Cleveland to Toledo at 11 PM.

Anyways, I can give that a try. Any idea where I can obtain silica packs, besides from a shoe box? Would putting the capsule in a sealed container with something like baking soda help in drawing out moisture?

Thanks for the suggestion. Any others?

 

[Marik]

Try a container with rice or dry beans. The soda wouldn't be a good thing to do because of dust--it's a powder. I heard you can get this silica thing at photo stores.

Good luck and let us know if it helped.

 

[Adam P]

Would a slice of bread work? I'm not sure if I have any beans or rice around.

Edit: Nevermind. I put the capsule in a little Tupperware container with some white rice. Any thoughts on how long I should leave it? 12 hours? Overnight? A couple days?

 

[Adam P]

Well, I just tested my 012 capsule after leaving it in a Tupperware container with some rice for around 12 or 13 hours. I plugged it in and turned my mixer on and left it on for about 10 minutes, talked into the mic, jacked up the gain to pick up room noise (the TV is on), shook it, tapped it, waved it around, and it sounds fine, so hopefully thats all the problem was. I think from now on I'll start keeping some sort of absorbent pack in with my mics. I keep them in a trunk, and I only have maybe 12 or so, so it should keep them all moisture free (hopefully). Thanks a lot for your help!

 

[Marik]

Good! I am glad it was of help.

<so it should keep them all moisture free (hopefully).>

Moisture and capsules don't get along well.