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DIY Conversion of Sennheiser HD800 Headphone Cable From Unbalanced to 4 Pin XLR

phoenixdogfan

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I have a pair of OG HD800s which came with a very nice unbalanced cable, but no balanced one. I recently priced out HD 800 cables and the cheapest I could find was around $125 from Etsy. Sennheiser wants $375 for their own cable. Since the HD800s are terminated with a unique proprietary cxonnector at the headphone cup, I think a lot of these dealers feel they can charge whatever they want to b/c of the lack of a universal replacement.

My alternative would be, I believe, to simply rewire the plug at the amplifier end for 4 pin XLR. Amazon has a very nice Neutrik plug for $8.95. So it represents an enormous saving for what should be just a soldering and assembly job.

If I cut the plug off the existing cable I think I'm going to find a L+ and L grd and a R+ and R grd. I have a chart listing how the 4 pin XLR is numbered. So my only real question is how the wires will look in the cable jacket. How are they color coded? Will the ground just be a copper jacket which I divide between the Left and Right gtound pins, or will each ground have a specific color coded wire. I have no worries about the soldering or the assembly or the XLR plug, but I just need to know how to identify which wires to solder to which pins, and it is a little different than a three pin xlr. Any help will be appreciated. I'd like to save a few bucks here, and the price of these cables is obscene IMHO.
 
You can just tone out which contact goes where by using the continuity function on a basic multimeter.
 
I made a short balanced cable for my HD660s by buying a cheap Sennheiser 3m cable, cutting it down to 1.5m and soldering a 4.4mm pentacon connector on the end. You could do the same, but replace the pentacon with an XLR (which is a lot less fildly than the pentacon) and replace the HD6xx connectors with some HD800 ones.

This was the cable I used: https://www.amazon.co.uk/gp/product/B0028PGXRE/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Thanks, but I already have Senn's highest quality cable, and I certainly don't want to buy and solder the HD 800 connectors to another cable. I just want to cut off the trs cable, tease out the 4 wires, determine which goes where, and solder them to a Neutrik 4 pin XLR. Should take around 5 minutes and cost around $10 if I can get the information to do it correctly. Not to mention saving $360.
 
You can buy a pair of HD800 connectors for £15, why risk cutting up and damaging your original cable, when you can make a complete new one for about £30? The cable I linked to is an original Sennheiser part, BTW.
 
Will the ground just be a copper jacket which I divide between the Left and Right gtound pins, or will each ground have a specific color coded wire.
I don't know what you'll find but a balanced connection doesn't have a "ground" and there can't be any common connections. You need 4 separate wires.

If there are only 3 wires a the TRS end, you'll have to go-back the L/R "split".
 
I don't know what you'll find but a balanced connection doesn't have a "ground" and there can't be any common connections. You need 4 separate wires.

If there are only 3 wires a the TRS end, you'll have to go-back the L/R "split".
Which could entail cutting up the cable who knows how far. Guess I'll just shop for a balance bargain cable.
 
Good luck...

Guess I could cut off enough of the TRS end, strip it and use the multimeter to check continuity. Don't know if I can rely on "red" being right and "green" being left, though I would think that's the common sense way to do it. Senn of course probably want to discourage DIYers, so it can charge $375 for a cable made with four 32 guage conducters, :(
 
You can just tone out which contact goes where by using the continuity function on a basic multimeter.
and usue a 15v batterry to confirm
Guess I could cut off enough of the TRS end, strip it and use the multimeter to check continuity. Don't know if I can rely on "red" being right and "green" being left, though I would think that's the common sense way to do it. Senn of course probably want to discourage DIYers, so it can charge $375 for a cable made with four 32 guage conducters, :(
A small 1.5V AA/AAA battery connected to the driver will cause the driver to go in or out depending on the phase/connection. This can be used to determine the left and right and the phase. Don't use a large battery because there is lots of current available and that might damage the voice coil. Perhaps @solderdude can chime in on that because I am not sure what the current capacity is of these small voice coils. Is a AA/AAA battery OK for checking headphones?
 
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and usue a 15v batterry to confirm

A small 1.5V AA/AAA battery connected to the driver will cause the driver to go in or out depending on the phase/connection. This can be used to determine the left and right and the phase. Don't use a large battery because there is lots of current available and that might damage the voice coil. Perhaps @solderdude can chime in on that because I am not sure what the current capacity is of these small voice coils. Is a AA/AAA battery OK for checking headphones?
Yeah, I thought of that too. And that is also my concern regarding using it on the drivers end.
 
and usue a 15v batterry to confirm

A small 1.5V AA/AAA battery connected to the driver will cause the driver to go in or out depending on the phase/connection. This can be used to determine the left and right and the phase. Don't use a large battery because there is lots of current available and that might damage the voice coil. Perhaps @solderdude can chime in on that because I am not sure what the current capacity is of these small voice coils. Is a AA/AAA battery OK for checking headphones?

A lithium button cell would be a safer choice.
 
Which could entail cutting up the cable who knows how far. Guess I'll just shop for a balance bargain cable.
These aren’t “bargain” cables, but they’re very nice and not unreasonably priced for the quality. Be aware that they’re modular cables, so you’ll need to also choose an interconnect for the end opposite the headphones.

 
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Some 30mW 32ohm drivers will be killed quickly with a 1.5V battery as this is 70mW in DC !
For 300 ohm headphones it is not a problem.
You can see the absolute phase when you remove the dust filter.

I would measure the cable only middle pin = + or have a listen and if it doesn't sound right reverse polarity on one of the connectors.

For XLR 4-pin: 1= L+, 2=L-, 3=R+, 4-R-
 
Why not try this https://drop.com/buy/massdrop-sennheiser-hd6xx
And this
Doesn't help. That's for a cable that's balanced but terminated in 2.5mm. OP has unbalanced cable terminating in a 3 wire TRS 1/4 inch or 1/8 inch
 
Which could entail cutting up the cable who knows how far. Guess I'll just shop for a balance bargain cable.
Would be my advice. But do you need to run them balanced, the THX789 should be ample for them.
 
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