foam for microphone grills

I had a couple of old EV635As laying around, and I took them apart and saw that they had a layer of foam underneath the grill. It was pretty nasty and coming apart. Is there any particular type of foam that I should replace it with? Can I just find something at the hardware store or the fabric store which would be good?

Thanks,
mike

I've used stuff from the fabric store - automotive headliner (the stuff on the ceiling), which is fabric and foam. The fabric peels off easily enough, and the foam is open-cell.

If using these in a studio I would just get rid of the foam and use an external pop-shield if you need it.

Behind the foam there is also a metal mesh and then a gauzy sort of material. Would you suggest removing all that as well?

I might do a little bit of experimenting. I never actually thought about how this foam affects the mics, it'll be a learning experience..

[quote author="mike_relay"]Behind the foam there is also a metal mesh and then a gauzy sort of material. Would you suggest removing all that as well?[/quote]

Possibly not. It may make a difference. You may be able to hear the difference or not. I find old foam to be a real problem because it disntergrates and craps up the element. You should try cleaning foam particles from a ribbon - not always a simple job!

I might do a little bit of experimenting...... it'll be a learning experience..

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Great idea! :thumb:

Hello,

Did anybody ever do some comparison or measurements with & without the internal foam inserts ?

I realize that without specifying which type of mic, this is is a very broad question.

I'd assume though that influence of foam inserts is taken into account for mic designs.

Understood the damping enters somewhere > 7kHz, but that's just from reading it somewhere.

zebra50 said:

If using these in a studio I would just get rid of the foam and use an external pop-shield if you need it.

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Sounds good, temped to do this for some older (BeyerDynamic) mics with crumbled foam inserts,
since they're just rarely to be used for vocals anyway.

W.r.t. popping, we're just talking about vocals, right ? Never experienced those kind of plosives for other sources.

Bye,

 Peter


PS Couldn't help spotting this is my 5532th message  ;D

Wow, this is an old thread!

I was just talking about vocal popping, yes.

I'd assume though that influence of foam inserts is taken into account for mic designs.

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One would think so! I don't really have an issue with the sound, but the crumbly foam is a pain.

I've recently rebuilt an RE20 - those actually use the foam to support the capsule, so you can't get away without it.

zebra50 said:

Wow, this is an old thread!

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You bet !  Receiving a few old dynamics with old foam I couldn't imagine this wasn't an universal problem, so I thought let's hit search here.

I was just talking about vocal popping, yes.

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Thanks for confirming. Other uses might then experience some little more highs but that won't hurt.

I'd assume though that influence of foam inserts is taken into account for mic designs.

Click to expand...

One would think so! I don't really have an issue with the sound, but the crumbly foam is a pain.

Click to expand...

You're right, leaving the old stuff in is no option.  I was actually so stupid to mess up the foam inside the grille of a Beyer M200N(C).  It might still been in perfect shape, had I not touched it. But it'd have been waiting to fall into pieces anyway...

There's for some mics also some foam on the capsules themselves, partly present. I'd rather not touch that for now.

I've recently rebuilt an RE20 - those actually use the foam to support the capsule, so you can't get away without it.

Click to expand...

I saw stories about that when searching for info yesterday yes. That's indeed bad news - and perhaps not, since it will have made solutions available.

OK, go foam go!  8)

Bye,

  Peter