The 3.5mm audio plug broke off on my Beyerdynamic headphones. I need to replace the plug. There are four conductors but I don't know what type of plug to buy (4-pin?) or what the pinout is.

Might be a plug and socket mismatch. A headset with microphone has a single plug with 4 contacts or dual plugs for headphones and microphone. The socket can be either a single with 4 contacts for headsets or dual sockets for headphones and microphone separated. Do you need an adapter cable?

beyerdynamic Spare parts - Headphones & Headsets

north-america.beyerdynamic.com/shop/hah/spare-parts.html

Items 1 - 40 of 53 - Cable Assambly for DT 108 / 109 ... Ear cushions pair, black, for T 51 p ... Ear cushion / black velour / one set / replacement ear pads for T1.

Dismantling the Beyerdynamic T1 for the 1st time - YouTube

? 5:21
https://www.youtube.com/watch?v=XC72mCFOIWo
Jun 19, 2013 - Uploaded by Jason Rhys-Thomas
Here is a quick vid of the dismantling process for thebeyerdynamic T1 - I ended up having ... I will be re-cabling them with SPC shielded cable.Missing: drivers

Hey benblay7. Cutting the wire was not stupid at all.

Two of the wires are ground and are tied together and soldered to the ground terminal. These should be the same color, usually a shiny copper color. The ground is negative. The tip of the plug should be wired to the left side and the center is, of course, the right.

Check this out: explainthatstuff.com/howtorepairheadphones.html

Good luck from Detroit, MI.

I'd start here http://north-america.beyerdynamic.com/service.html
you should be able to find local/area outlets or order direct.

Hi,

The audiolevel is much to low for a headphone.
You really need to use a headphoneoutput ( if its there) or a headphoneamplifier.
You tried to connect your headphone on line-level outputs.

Regards,
Gerard

Hi,

Take a look at this link.
http://www.cameratim.com/reviews/audio/beyerdynamic-headsets/

Regards,
Gerard

Hi,

Just contact Beyer-Dynamic in Germany.
They will help you out.

Regards,
Gerard

First check the cable and plug they can very easily break. Sometimes bending and flexing can cause the sound to appear. Try this all over right to where the cable joins the headphones. The only other problem it can be is a failure of the speaker. UNLESS there's a volume control or a switch in the cable or on the phones themselves. These can break or get dirt on the contacts cutting sound off.
PS Make certain they don't work in other amps first, headphone sockets can breakdown too!
If you find it is the plug, you can cutt it off and fit a new one if your any good with a soldering iron. The cable is much harder as you would need to get into the headphones to replace it. If the speaker has gone you would need to order one from Beyerdynamic.
Dirt can be cleaned out with Servisol Switch Cleaner.

If you know how to solder wires then the cord is certainly replaceable. My cat chewed through the cord on my BeyerDynamic headphones, but I was able to order a replacement from them, take the earcups apart, remove the old leads and solder in the new cord lines.

You could try calling the customer service line for Sennheiser and see if they can send you a replacement, or you could just pick up a generic cord from Radio Shack or an electronic parts supplier.

A USB cable????? How about just a regular audio cable. Plug one end into the audio input on the monitor and the other one into the audio output (usually green) on the back of the tower.

One just like this.