I bought an NT2 second hand about 6 months ago and came to use it today, and it's suddenly really noisy, to the point where it's almost hard to hear my voice. I can only describe it as sounding like i'm recording someone rustling a crisp packet right near the mic and the voice being about 6 feet away.
My quandry is this, do I look into getting it repaired (if so where?) or do I just bite the bullet and sell it as faulty (I got it for £60). Is the mic worth spending the money to get it fixed as i assume it'll be about £70 to fix, and the price of a NT1A is only about that 2nd hand?
Just to clarify it's the original NT2 that looks like the Neumann that they got sued for and had to discontinue...... .
It is almost certainly a combination of moisture and contamination (dirt) either on the capsule or on a sensitive part of the electronics. This is almost certainly repairable as it is a very common problem but the first thing to do is to try drying the mic out first - either by gently warming it in an airing cupboard or by storing it in a closed container with some dessicant (or rice) to remove the moisture.
Assuming that it is condensation, the question is where are you storing it so that condensation can occur? If it's kept in a warm room, then it's unlikely to get any condensation on it. If a cold room, then into the warm, then yes, condensation is quite likely.
Is it kept in a smoking environment? Bad for mics (and bad for you). Or lots of scented candles? These can leave oily films.
I keep but my mics go a case I bought from Jessops year's ago where you cut out the foam and then store this under my desk in my studio (or front room as my wife likes to call it). Probably not condensation then? We are both non smokers (which is handy when it comes to selling things on). Anyway, it's currently sitting in my airing cupboard at home in a sock (which looked like something in a prison movie when I walked across the landing with it this morning)
Anyway, if it it dirt, any tips on how to clean it (camera lens brush?) I've already had it open to check before to see if there was anything obvious before I doted out it might be dust etc..
I'd wait and see of it gets better after a gentle drying before attempting a clean.
Capsule diaphragms can be cleaned VERY gently with de-ionised water and a fine brush, and then dried thoroughly... but it is a skilled job and damage is highly likely if you're not extremely careful. Dust and dirt around the front end of the impedance converter circuitry can have the same effect.
Diaphragms can get dirty if the mic is used as a close vocal mic without a pop-screen -- moisture and food debris from the mouth splatter through the grille, and then act to trap atmospheric moisture and generally create a leakage path for the charge built-up in the capsule.
To be honest, if it is a dirty capsule, cleaning is unlikely to provide a long term solution -- a new capsule is almost always a better bet, but only if the economics justify it which they probably won't in an old NT2... unless you're into microphone DIY and want the experience of swapping capsules!
The other possibility is a failure of the electronics in some way -- failing electrolytic capacitors is a strong possibility, or failure of the front-end FET -- they can often go noisy with age. If drying out doesn't help, this is probably the most likely cause.
Technical Editor, Sound On Sound...
(But generally posting my own personal views and not necessarily those of SOS, the company or the magazine!)
In my world, things get less strange when I read the manual...
I ain't going to touch no diaphragm. I do soldering for mic leads in my workshop (or "kitchen" as my wife insists on calling it), but that's as far as my tampering goes.
I'll possibly make some money back if I sell as possibly faulty to some tech geek, so not all lost.
Will see what it's like in a couple of days. If not, I can always keep it in the sock and use it as a weapon if ever sent to prison for a crime I didn't commit......
The drying trick can be very effective. When I bought my brand-new pair of KM184s I plugged them in and they crackled like nobody's business. I nearly panicked. Fortunately common sense intervened and I gave them a couple of days in the airing cupboard and they've never given trouble since.
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