Microphones - longevity?

[casapete]

Okay, simple question - do mics wear out?

Had a couple of Shure 58 Betas now for quite a while , one of them say maybe 20 years, and was just

wondering if they have a finite lifespan. Or is it one of those things where they deteriorate so slowly

you just don't notice ?  They both sound good to me, and are always looked after, never been dropped etc.

Take the mesh/grille off every now and then and clean them, so look okay too.

Any thoughts?

[Dan Dare]

As long as they're looked after/not abused, they don't seem to deteriorate - dynamics at any rate. I have a SM58 that must be at least 30 years old it still works fine. Not sure about condensers, although you see some of the old Neumann valve mics going for crazy sums, so I guess they must last too. If they still sound right, they must be OK, I guess.

[Happy Jack]

I've had an old SM58 'lose sensitivity' over time, which might itself be age-related, but the identical SM58 next to it in the box is still working perfectly five years later.

[whizzzy]

The only thing that I've found that can deteriorate is the foam pop shield that they insert behind the metal windshield on the likes of the SM58 and some AKG mics. On my AGK 5900C's the foam shield has started to crumble on a few of them and so I've bought up some stock to replace them in the future. Probably a good idea for hygiene reasons as well. 

[Tubster]

Much depends where they have been used IME. I bought and used a number of 58 and b58s in Florida over 13 years. When I got them back to Europe, 2 b58s had failed due to corrosion. We are talking super high humidity.