Question about Sennheiser MD421-II Professional Microphone

2 Answers

Dead md421 Bought it for $10 and it's dead. How do I take this thing apart to get inside? Is there any way to get an exploded view of one? Thanks

Posted by on

2 Answers

  • Level 1:

    An expert who has achieved level 1.


    An expert whose answer got voted for 2 times.

  • Contributor
  • 1 Answer
Re: dead md421

Ignore GazllFixIt...

If it's dead, a connection is already broken inside.

Much more unlikely is that the capsule is at fault - and if it is you can't make things any worse anyway.

Who cares if you break a connection when you take it apart - as long as you can use a soldering iron, it's easy enough to fix. If you can't, why would you be taking apart in the first place ;)

You'd be mad to send it to Sennheiser to solder 1 or 2 points then send it back to you! Waste of time and money.

Try learning something yourself, especially if it only cost $10 and doesn't work to begin with.

Remove the capsule assembly - desolder and disconnect the wires at the base of the mic (not from the capsule) yourself (see, opposite of last advice), then connect them directly to a cable with an XLR on the other end. Forget about ground for now.

Now plug it you hear anything? If not, get a multimeter and check continuity between capsule and your XLR. If you have continuity, throw the mic out. If not, replace those wires. Still nothing - chuck it out.

If you are hearing something (it should sound absolutely fine, clear, loud etc), ...find the broken connection elsewhere...but also, be happy because it definately still works and is definately fixable and you can do it yourself.

Posted on Jul 24, 2008

  • Level 2:

    An expert who has achieved level 2 by getting 100 points


    An expert that got 5 achievements.


    An expert whose answer got voted for 20 times.


    An expert who has written 20 answers of more than 400 characters.

  • Expert
  • 103 Answers
Re: dead md421

A microphone such as the MD421 does sound too good to be true for $10!

I would strongly suggest you do not try to take it apart as the connections inside will be destroyed. I know people that have had a go at taking it apart & destroyed their mics, ended up sending them back to Senheiser & having to pay more to get the extra damage fixed. It really is a false economy.

There's some info here:

...scroll down for techical data sheet & manual.

Posted on Jan 08, 2008

Add Your Answer

0 characters

Uploading: 0%


Complete. Click "Add" to insert your video. Add


3 Points

Related Questions:

1 Answer

Need to take it apart to replace the grill


First you must loosin the connector.
There's a little shield with the serialnumber you can slide away.
Underneath that you will find the screw to loosin the connector/filter.
If you look inside you will find a bolt, unscrew that one and the element and grill will seperated from the housing.
Thats what I remember after 25 years.

Good luck,

Apr 23, 2011 | Sennheiser MD421-II Professional...

1 Answer

My MD 421 suddenly has no high end. Sounds muffled and distorts when I yell into it.

Check the cable. It maybe damaged. Check your phantom power. If your going to yell into the mic...Turn the input gain down to avoid initial distortion. Not sure of your recording setup, but everything in the chain input to output is key.
You can probably assume the mic to be damaged if these things dont check out.
I have a MD 421.

Mar 31, 2011 | Sennheiser MD421-II Professional...

1 Answer

5 of my 8 md 421's have developed a fluttering sound on impact of any tom! Yet they sound normal on a human voice? This sound is not like any distortion I'm used to hearing. These mics were purchased in...

Sounds like the membrane hooks on to something at high SPL's. And perhaps especially at low/low-mid frequencies. You most probably need them taken apart and have them examined.
That 5 of 8 has gone bad makes me believe it related to something that weaken with time. Say, foam going dry, tape losing its grip, rubber going stiff.
Could be an easy mechanical fix, but yes, one would have to take them apart and examine them closely.
I would ask for a service quote directly from sennheiser. They are lovely mics, and may well be worth the effort.

Mar 05, 2011 | Sennheiser MD421-II Professional...

1 Answer

Is there a pad on the md 421-u

No, just the high-pass filter sleeve.
Sorry, Cody J.

Dec 15, 2010 | Sennheiser MD421-II Professional...

1 Answer

How does one take a Sennheiser MD 421 apart?


At the connctorside there's a small metal plate with a serial number.
You have to bench it a little, underneath there's a screw.
Unscrew it and you can take the connector out.
What I remember after 25 years is that there is a screw inside which is loosing the grill and element.

I've written it before with succes.


May 17, 2010 | Sennheiser MD421-II Professional...

1 Answer

I have to shake it to get a signal. Seems like a bad connection. Used very little in a home recording studio.


It could be a dirty switch, you can find this switch at the back of the 421. You can rotate it several times to clean the contacts a little bit. Otherwise you have to take the 421 apart.

Good luck,

Dec 31, 2009 | Sennheiser MD421-II Professional...

1 Answer

How to open a vintage sennheiser 421hl

Try contacting them here: Have a look at the bottom end of the microphone where the cable connects. What are the four holes for? I don't have one to look at but I do remember working on one about 20 years ago. Also I seem to remember that the side rails slid back. I hope this helps.

Nov 27, 2009 | Sennheiser MD421-II Professional...

2 Answers

Shure sm58

Hi danny

There not that much to take apart on the sm58. On page 2 of the user manual there is a wiring diagram to reconnect wires. the grill wind filter part screws on. The socket on the bottom is secured with a screw.
I am more than happy to answer any other questions you may have about it, please get back to me here, or use the ASK function to go straight to me :) If you are still unsure, have problems, or we need to look at the situation more deeply, then before you give a rating for this advice, hit the ASK button Thanks for using FixYa, If you consider the advice I have given you as sound, a FixYa rating is a great reward for my efforts to help you. Cheers.

regards robotek

Jun 23, 2008 | Shure SM58 Professional Microphone

1 Answer


first use hair dryer for a minute if you have.
second- bring any box with suitble size to mic and put a rice on it and put the mic on it for a couple of days{rice absorb wet and humidity}

Dec 05, 2007 | Sennheiser MD421-II Professional...

Not finding what you are looking for?
Sennheiser MD421-II Professional Microphone Logo

Related Topics:

691 people viewed this question

Ask a Question

Usually answered in minutes!

Top Sennheiser Microphones Experts


Level 2 Expert

611 Answers

Mando Mojica
Mando Mojica

Level 3 Expert

643 Answers

Are you a Sennheiser Microphone Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides