[FraGGleR]

In anticipation of an incoming CEntrance HifiM8, I decided to switch to a balanced cable for my portable of choice, the Sennheiser Momentum.
 
Only problem is that there is a TRS 2.5mm jack on only one side, so while making a new cable is a breeze, it wouldn't be balanced.  Since I didn't want to risk marring the looks of the Momentums by drilling to each driver, I decided to see what I could do to the jack.  I wasn't thinking tutorial, so I only have a couple pictures, but the great news is that the 2.5mm jack is mounted to a PCB that is easily unscrewed from the driver and can be easily de-soldered if you have a solder pump.  Once the 2.5mm jack is removed, you have 4 very convenient places to solder the new cable to, including separate grounds (they were joined inside the jack, not on the PCB).  All in all, ended up being easier than I thought it was going to be due to the extremely convenient PCB.
 
Here is a picture of the board with the 2.5mm jack already removed:
 

 
Here is the back of the board after soldering wires to it:
 

 
Ready to solder the drivers back onto the board (that is hotglue on the board used for strain relief while braiding the cable):
 

 
Finished with a mini-XLR:
 

 

[GSARider]

Very nice! Now all I need is for someone to mod the earcups to a larger size,

 

[Armaegis]

Is there anything holding down the new cable other than the compression from the cup?

 

[FraGGleR]

The board is screwed down, hotglue at the solder joints as well as a little on the heatshrink where it hits the cup.  Other than that, all compression (which is considerable).

Oh, and the board is through-hole instead of surface mount so there is a little more security from that as well.

 

[Dubstep Girl]

Quote:

 

 
beautiful cable/headphones!

 

[Komkrit]

Cool !
 

 

[Armaegis]

Hey, congrats on the front page!

 

[FraGGleR]

Thanks, all!

 

[Jupiterknight]

Excellent info. I was thinking about doing something similar with my Beyerdynamic DT1350 to combine it with my incoming M8 as well 

 
One question, does the M8 actually take a mini XLR ? I thought the options available are only regular sized XLR or do you plan to use an adapter? 

 

[FraGGleR]

No. As much as I wish the M8 was going to have a mini XLR option, this is so I can use a set of adapters that I made already.

 

[Jupiterknight]

That's what I thought and I completely understand your preference.  I wish as well that the mini XLR option would be available for us to choose. Anyway, excellent mod and indeed very helpful. 

 

[Armaegis]

I would love to make an adapter set like that, except it's friggin impossible to find mini-xlrs in Canada, much less than 4-pin ones. 

 

[livewire]

What was your choice of cable?

 

[ukaudiophile]

I love the idea of doing this to mine but am not feeling brave enough lol

 

[wes008]

 That might have just sold me on the Momentum. Except I have no DIY experience