They say mattresses and underwear are non-transferable. I kid, but you see the logic. S'kinda like trying on someone else's sweaty baseball cap or using your friend's toothbrush.

Obviously, used microphones are bought 'n' sold all the time on ebay and gear exchanges, but how do you know that mic hasn't been the recipient of accumulated expectoration over the years?

Even more important, how can you make sure you're not ruining your own favorite microphone with neglect?

The catalyst for this article comes from a bad habit of ignoring the dust in my studio. It's a converted closet with shelves, electronic equipment, plenty of acoustical foam, and an open door when I'm not in it. 

Aside from that, it's important to note that I live in Las Vegas, one of the windiest and dustiest cities in the Northern Hemisphere. Left untouched, a fine film of dust can form in a week, more if it's windy.

One good thing, though, is that it's dry dry dry here. Recently it was 1% humidity (one!). 

Know your environment.

High humidity regions can be a contributor to electronic device degradation - including mics. Drastic changes in temperature and humidity should be avoided for your expensive condenser mic. Foam mic filters and windsocks begin to wear, and the filaments and particles can fall off and into your microphone, clogging the capsule.

Cigarette smoke can diminish the performance of a good mic over time, too, and since large-diaphragm condenser mics are designed to be sensitive to tiny changes in air pressure, they should be kept away from drafts, and things like slamming the lid down on it's wooden or plastic case when storing.

It's common to see mics in professional studios being kept under a plain clean plastic baggie - open at the bottom - when not in use.

Dynamic mics? Meh.They're tough. Pretty hard to abuse one of those with considerate daily use.

Ribbon mics, just the opposite. They're the most fragile, and should be handled with diligent care.

And if you think your most precious voice acting tool is being protected by the foam pop filter it's encased in - better think again. Especially in dry environments, those foam filters begin to wear out, and the filaments and particles can fall off and into your microphone, clogging the capsule. 

Take it off, and shake it or lightly scrape it over a piece of white paper to see evidence of flakes.

Oh, and it's probably not best to try to pry open the wire mesh screen and clean a condenser microphone by yourself, unless you're George Whittam. That's best left to service professionals at the company that created the mic.

Sometimes they'll refurbish it for free, 'cause it's in their best interests to have their good reputation preserved. Sennheiser is a good example of that kind of customer service. 

However, over time, any good microphone grill can pick up particles, and if you suspect a mic is old, or you can SEE congestion in between the wire strands, it might be time to send it in for a professional cleaning.