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.

Beyerdynamic T5P Recable

Beyerdynamic is a family-owned audio equipment manufacturer based in Germany that produces headphones, microphones and wireless audio systems. The headphones produced by Beyer feature great build quality and the sound produced by their 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 the pricier Tesla-based models that Beyer introduced over the last four or so years: the T1, T5p, T50p, T90 and T70.

Beyer's Tesla lineup

The Tesla nomenclature comes from the redesigned transducers that achieve efficiency values of over one Tesla, which is the unit of measurement for magnetic flux density. This provides the listener with nearly double the volume at the same input level as typical headphones. Also unique to the Tesla line are the drivers which are angled toward the listeners ear.

Today I'll be recabling the luxurious Beyer T5p. The T5p is effectively the mobile version of the T1 (The "p" standing for portable) and with it comes a few changes, including a short 4 foot cord and a 32 ohm impedance which can be driven easily from sources like the iPhone / iPod and other portable music players, and leather pads to help attenuate outside noise.

Beyerdynamic T5p

Something I've found with some Beyer headphones (especially the DT880 / 250ohm) is the upper-midrange can cause me ear fatigue over long listening sessions. This certainly doesn't affect everyone, but a few other people with sensitive ears have mentioned the same finding to me. I've found the best remedy for this is to recable the headphone with Cardas enameled copper wire, which effectively warms up the sound signature and subtly rolls off those frequencies which I personally find fatiguing.

Cardas copper wire

The first step is to braid the Cardas copper wire in a litz-braid. I've chosen three different colors in this case, red for right signal, blue for left signal and black for ground.

Braided Cardas wire

The cable is then sleeved with the soft black nylon multifilament sleeving. You'll notice below that electrical tape is over the ends of the wire, this prevents the small conductors from snagging the sleeving while they are fed through by hand. 

Sleeved with black nylon

Once the leather earpad and sealed ring are removed, that gives access to the driver housing. Note the angled driver in the photo below. 

The T5p angled driver

Take a look below at the beautifully machined Tesla driver housing, I've never seen anything like it. 

T5p Telsa driver backside

The existing wire and solder is removed. This is done using as low a temperature as possible as to not damage the delicate drivers. Next the Cardas wire is prepped. The Cardas wire is enameled, so it has to be either dipped in a solder pot or heated up with solder on the tip on an iron to tin it and remove the enamel. Once appropriately tinned, it is soldered in place. 

Cardas wire soldered in place

Once the wire is soldered in place, a stain relief system and adhesive is used to keep the wires in place (and helps prevent the tugged cable from yanking on the solder tabs). The headphone is then put back together with extra attention paid to the sealed ring (the seal is very important to the sound). Below is the completed product. 

Recabled T5p

The T5p has a incredibly clear, detailed and coherent sound signature. Color me impressed. I hope you enjoyed this post, if you'd like to have your headphones recabled, please contact Zynsonix for a quote. Since Beyerdynamic T1, T5p, T70 and T90 are all quite similar, the same mods /recables can be performed on all of them. Here is a Beyer T90 that has been recabled for balanced listening with dual XLRs.

Beyerdynamic T 90 balanced with dual XLRs

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.