Beyerdynamic Balanced Removable 4 Pin Mini XLR Mod

A client recently sent me one of my favorite headphones to modify, a Beyerdynamic DT770. The DT770, DT880, DT900, and similarly the T1, T5p, T70, and T90 are all intuitive to work with and respond well to new cables and mass loading.

Beyerdynamic DT770 - Pro 80 ohm version

This DT770 would be getting a removable cable mod, which includes the installation of a mini XLR in the headphone cup so the cable can easier be removed for transport or to perhaps have separate cables for portable and home use. The DT770 has room for a mini XLR jack on both the left and right cups, however this user preferred the simpler single ear input. Since I was already going through the trouble, I wired the headphone for balanced operation just in case he ever switches over to balanced listening in the future. The great thing about mini XLR jacks is they lock, so no need to worry about them slipping out like a 3.5mm or 2.5mm. Also, TRS connectors can loosen over time, however this is not as likely with the mini XLR connectors.

Below is a look at the interior driver. As you can see, the DT770 driver is unique in that it has a felt and plastic ring encircling the center, which reduces the sound wave reflection inside the cups.

DT770 driver and felt/plastic ring

Because the felt and plastic circle reach the plastic backing of the cups, any added mass damping should be clear of interaction. Below you'll note the Dynamat Xtreme installed is a small circle which is measured to fit neatly inside the cup and not cause any clearance issues with the driver. 

Dynamat Xtreme used as mass loading

Beyerdynamics used to come with a round hole, but it's square now that they've revised the manufacturing to some extent. I carefully increased the size of the hole diameter toward the round side of the cup with a Dremel to prevent the plug from getting in the way of the driver. The hole does not have to be absolutely round as the ridge on the mini XLR plugs will cover minor imperfections. 

Dremeled hole for 4 pin XLR mini jack

A three or four pin mini XLR jack can be used. In this case I used a four pin as I wanted the user to be able to upgrade to balanced down the line if he wanted, but in other cases, a three pin can be used as the ground is wired shared as default. Please note the position of the jack, if it is not close to the rounded edge like this is, the driver will not fit back in. Dremeling down the metal casing of the jack where it meets the driver may help a little bit, but will reduce the integrity of the jack if too much is taken off. 

Nice, clean fit

Wire should be run from one side of the headphone to the other as this is going to be single entry. A twisted pair of Zynsonix Xev silver clad wiring is prepped and sleeved with black polyolefin heatshrink tubing. 

Wire to run from one cup to the other

This can be wired however the user prefers, however I used the XLR standard (pin 1 = left +, pin 2 = left -, pin 3 = right +, pin 4 = right -). 

Wired with Zynsonix Xev silver clad wire

Before re-installation, the driver solder tabs are cleaned of the stock solder.

Solder tabs cleaned of original solder

The new Zynsonix Xev wires are installed using fresh Cardas silver content solder and the felt/plastic cups re-installed. 

Driver wired up and ready

The foam is reseated on top of the drivers and the earpads are reinstalled, so we have a nice clean 4 pin mini XLR input on our Beyerdynamic DT770 now. 

Installation of mini XLR jack complete

And finally we have the finished product featuring some cool colors, in this case rust with a black accent, terminated with a Switchcraft gold plated mini 3.5mm plug and a Neutrik / REAN mini XLR. Now these old Pros are ready for some stylish listening! 

I hope you enjoyed this post, please contact Zynsonix if you have a pair of Beyerdynamics (or any other headphone) that you'd like recabled or modified.

For more full-sized Beyer headphone mods, check out the Beyerdynamic T5p Recable and the DT880 Recable.

The Fine Print:

The above steps detailing the modification and re-cabling of a headphone are for entertainment purposes only and not to be performed under any circumstances. The owner of this blog and all associated parties can not / will not be held responsible if you attempt the process posted and cause physical harm to yourself, your surroundings or your property. Please keep this in mind.

Recabling a Pair of Beyerdynamic DT880 Headphones

Beyerdynamic is a family-owned audio equipment manufacturer based in Germany that produces headphones, microphones and wireless audio systems. The headphones produced by Beyer are very solidly made, I'd imagine the rugged designs have the travelling DJ in mind. Still, the sound produced by Beyerdynamics top-tier headphones is something the discerning audiophile can really appreciate. The DT770, DT880 and DT990 models are ideal choices for the listener on a budget, and if one likes what they hear, there are pricier Tesla-based models that Beyer has recently introduced, namely the T-1, T-5p, and T-70.

The Beyer DT770, DT880 and DT990

The differences between the 770, 880 and 990 are surprisingly not subtle. The DT880 tends to be the most chosen for neutral listening, it is a semi-open design and has the most well-balanced presentation of the three headphones. The DT770 and DT990 are much more bassy, with the heaviest bass response coming from the closed DT770. The fully-open DT990 seems to have slightly less bass and a wider soundstage than the 770. I personally think that the 770 is the ideal movie and gaming headphone, the 880 is the best for analytical listening, and the 990 is good for audio enthusiasts who need a fun-to-listen-to headphone that matches a typical speaker system's bass response. 

While the sound of each headphone varies, the process of recabling them is nearly identical. Aside from the driver and cup design, the headphones appear to be identical inside and out. For this post, I will be recabling the Beyerdynamic DT880 headphones. Below is a stock DT880.

The Beyerdynamic DT880 Headphone

The wire for recabling a Beyer and still keeping the single-entry look takes a little bit more care than a typical headphone cable. When braiding, the wire should go from a litz braid to two twisted pairs about 2 and a half feet from the end. One of these pairs is nearly trimmed off, only leaving enough wire to get to the driver within the cup. The other twisted pair will be run through the headband. 

The braided Beyerdynamic cable

The wire is then sleeved and the long twisted pair gets some heatshrink to distinguish each side. 

Sleeved Cable

Then a four pin Neutrik connector is attached for balanced operation. If you are interested in reading more about 4 pin balanced connectors, please check out my post creating a 4 pin to TRS adapter cable. 

Cable terminated with a Neutrik 4 Pin XLR

Now that the cable is ready, the first step to getting inside the headphones is to remove the velour pads. These pads stretch over the frame of the cup, so there are no screws to remove, etc. You will notice a number of perforations on the inside of the pads, these holes make a big difference in the sound, covering them adds unwanted reverberation. If one replaces the velour pads with leather, it is preferable (in my humble opinion) to get the leather pads with the perforations inside. 

DT880 pads removed from the cups

The next piece is removed using a typical envelope opener to pry the plastic ring out of the cups. The plastic ring retains the driver and driver surround. Once it has been removed, one has access to the driver terminals. 

DT880 driver and driver terminals

There is generally a marking on the driver to determine the positive side. In this case it is a yellowish gold mark. I take the time to use a multimeter and verify this is the case before snipping off the stock wires. The left driver has three terminals, the center is the right signal which is not electrically connected to the driver but the wire that runs across the headband is connected to this terminal. The ground is also run from the ground of the left driver to the right driver. This is all removed and ignored as dedicated wires will be run directly to the drivers in the recable. This will remove unnecessary solder joints in the signal path and isolate the ground for balanced operation. Below is a photo of the shell of the DT880 stripped and ready for the recable. 

Beyer DT880 Shell

The latest models of the 770, 880 and 990 have a square opening that the stock wire is fed into, This square hole needs to be dremelled out so that it is round, then heatshrink built up on the new cable for a perfect fit. A custom retaining system is set in place to keep the cable from being tugged out of the cup. 

Wires soldered to the DT880 driver

The wire is soldered to the driver terminals with the assistance of engineer helping hands. The wire is then fed through the little grommet to the other cup. The headband is now placed over the wire and sealed back up using the zip-lock bag type mechanism. 

The wire is fed through the little grommets in the cups

The second driver is soldered on the same way, and we have a complete headphone!

Completed headphone

This headphone also has a balanced to single ended adapter so it can be used with both types of amps. 

Another angle

I hope you enjoyed reading this post. If you'd like your Beyerdynamic headphones (or any other headphones) by an experienced recabler with some excellent sounding cable, contact Zynsonix. Since the 770, 880 and 990 are all quite similar on the inside, each can be modded / recabled the same way. Here's a Beyerdynamic DT990 PRO with a recable with both a standard mini and a Pono output to maximize utility out on the road. 

Beyerdynamic DT990 modded with new cable, mini and pono connectors

The Fine Print:

The above steps detailing the recabling of a headphone are for entertainment purposes only, and not to be performed under any circumstances. The owner of this blog and all associated parties can not / will not be held responsible if you attempt the process posted and cause physical harm to yourself, your surroundings or your property. Please keep this in mind.