Hey,
Just bought a Sennheiser MD421U from ebay the other day, and just got chance to test it on some drums today and it seems really thin. I know they have the High Pass Filter on them but it's set to the "M" setting which should give most bass.
It's the older "U" version, does anyone know if these are considerably different tone wise? Or are they wired differently?
If anyone has any help, please let me know, CHEERS!

Hi David,

That doesn't sound too good.

I have a few MD421 mics. They are bright - they have a rising frquency response. Is yours bright or is it actually lacking in bass? It should sound fairly full if you speak directly into the grill - if it still sounds bass-light then I would suggest there may be a problem.

There are variations in models, but the general response of all of them is fairly similar. The U model is not that early. Some models (HL I think) are high impedance - this could cause bass loss, but probably not.

The most common problem would probably be a shagged capsule. Another problem which is a lot more simple is broken wires inside the mic or at the connector end.

If you think your mic has a problem, you should definitely contact the seller. If they are no use, you can get a refund from Ebay or Paypal if you used them.

Good luck,

Roddy

I'm thinking the wiring might be suspect. Mainly because that would mean the capsule is ok! But also because it was making some crackling sounds earlier on when I was setting it up. When I wasn't moving the mic at all. I've read some complaints from people on other forums who mentioned the same/similar problems which did stem from wiring. A few rewired, bypassing the Low Cut, and had much better signals. I'm gonna swap it out tomorrow and have a look at the wiring. Although I hear they're not that easy to dessasemble but it's worth a shot, I got it cheap but not cheap enough to just forget about it.
Thanks for your help.

There is an exploded parts diagram on the net somewhere. It is hard to find.

Be careful when removing the socket - do not twist it when removing or you will break the wires (which I did). It has a funny method of removal depending on whether it is tuchel or XLR.

Hope it goes ok,

Roddy

when you rotate the selector to different filter settings, do you hear any difference at all? if not, that would suggest that rewiring is necessary.

Thanks,
I'll test it again today. If I notice anything specific I'll let you know. It does pop when I twist the Low Cut though.

I just solved a similar problem...last year bought one from some guy in kansas really cheap....so the 421 showed up....cage all bashed in...sounded thin...switch busted (but I bypassed it, still thin)
I just ignored it...

so last month I sent it in to Sennheiser for $129 new capsule, cage, and switch and damn it sounds good...well worth it

You should contact the seller cause that's a bogus sell....but if it was cheap enough....send it to Sennheiser.

Hey guys,
I tested the mic some more today, I checked the switch end, and from what I could see it looked top notch, like never touched. So I looked at the capsule, and a weird thing showed up. Under one side of the grill, the inner, thin silver grill, had basically screwed up as if the out grill had come off at some point and whoever was using it couldn't get the inner grill back in properly. It was making contact with the terminals on the capsule itself, causing a short making horrid cracking popping sounds, and I guess drawing some signal away. I fixed that just by straightning it out and putting it back in. The sound of the mic HAS improved, at least it doesn't crackle. But to me it sounds thin, against what I know these mics sound like. I'll post a sample in a few minutes of what a bass drum sounds like through it.
I have emailed the dude I got it from, I got it for £90 so not bad, but if I could find an easy way of getting it fixed I'd be up for it. Unless he wants to sell me a better one for less, he's still got 5 421II's for £190 each.

OK so, PLEASE tell me if I'm mad cos just listening to this back home it didn't sound AS bad than at the studio today. It's a pearl bass drum recorded through an alesis desk, onto an ADAT HD recorder. No eq or compression. Does this sound right to you?
To me it doesn't sound as rounded to me. I substitued this mic with a Sennheiser e609, and it sounded far more clicky and boomy than this, it just sounds very middly to me. Let me know please.

THANK YOU!

David, I can't see a link for a sound file here.

I would still be careful, though. If it doesn't sound right, get your money back. I use Ebay a lot - a refund should not be a problem.

Incidentally, you can get yourself a nice white script-logo / early MD421 for less than £100 quite often. I've bought a couple for £100 for the pair. The key is to look in the right place.

The inner grill may have damaged the diaphragm on your MD421 by touching it. Or there may be something else wrong with it. Can you borrow someone else's MD421 to compare?