Cross talk reducing quad wire cable mod in headphones

[MagnetoSound]

They use a TRS plug - 3 contacts to either 4 wires or 2 wires plus shield. From memory the DT770 have 2 core and shield terminating at the left capsule - I have a couple of pairs I might pull one apart for a look inside. Hard to say with moulded cables.

3.5mm TRS as stock, yes, with a screw-on 6.3mm adaptor. I have replaced mine with female XLR-3.

They have a sort of ‘fig-8’ style curly cable, two wires in each section.

I wear them while tracking guitar all the time. I have never experienced interference through my guitar pickups, and I monitor fairly loud.

 

[RoadrunnerOZ]

3.5mm TRS as stock, yes, with a screw-on 6.3mm adaptor. I have replaced mine with female XLR-3.

They have a sort of ‘fig-8’ style curly cable, two wires in each section.

I wear them while tracking guitar all the time. I have never experienced interference through my guitar pickups, and I monitor fairly loud.

Yeah I know they have two different kinds of cable - curly and straight - mine are curly on the 250Ω ones and the other set has a straight cord - both hard wired - it’ll be interesting to see. I don’t think you would get enough current to radiate very far anyway to cause problems but some manufacturers have different ideas to others

 

[Tubetec]

Slightly off topic but seeing as starquad cable was under discussion ,

I had an idea to try starquad cable for spring reverb recovery ,
typical recovery circuits use an unbalanced phono connection with one terminal grounded .
I found the sound of springs is cleanest with a hi-z load on the transducer , I often use an active DI box with 5Mohm input and short patch cable for recovery and when located away from mains transformers and with extra sheilding on the reverb pan it gives good performance .

Lately I got the SSL2 interface which features fully balanced connection on the Hi-z input with very low noise ,
I was thinking of wiring the reverb output with a flying lead of starquad to TRS , it might cut down on induced noise over the unbalanced method and every db you reduce noise the more it reveals the low level details of the spring ,

I like to feed the recovered reverb signal through a Drawmer DS201 in Duck mode , then use the main vocal into the side chain to control the reverb swell , with correct settings of the threshold attack/hold/release dials the reverb dynamically swells in the spaces between the vocal lines , the sound doesnt get crowded by the initial clang of the spring , nor do things become lost in a washy mess, it just leaves auditory vapour trails in the gaps .
The same Ducking type effect is also excellent with ambience mics on a drum kit , for instance using the toms on the trigger inputs .

 

[Whoops]

Normal headphones use 2 core + shield anyway and the shield is grounded at the headphone amplifier. Can’t recall seeing headphones without shielded cable, domestic or professional.

Actually the oposite, normal headphones use 3 wires paralel to eachother not even twisted, 3 conductors, onde of the conductors is the return path connected to ground.
I fixed many headphone cables and I never ever seen a factory headphone cable with shield, it's always or 3 separate cables or 4 separate cables, unshielded.

From memory the DT770 have 2 core and shield terminating at the left capsule

I fixed today a cable of DT770 Pro headphones, and the cable is like I said above 3 conductors next to each-other, there's no shield in the DT770 cable.

 

[RoadrunnerOZ]

Slightly off topic but seeing as starquad cable was under discussion ,

I had an idea to try starquad cable for spring reverb recovery ,
typical recovery circuits use an unbalanced phono connection with one terminal grounded .
I found the sound of springs is cleanest with a hi-z load on the transducer , I often use an active DI box with 5Mohm input and short patch cable for recovery and when located away from mains transformers and with extra sheilding on the reverb pan it gives good performance .

Lately I got the SSL2 interface which features fully balanced connection on the Hi-z input with very low noise ,
I was thinking of wiring the reverb output with a flying lead of starquad to TRS , it might cut down on induced noise over the unbalanced method and every db you reduce noise the more it reveals the low level details of the spring ,

I like to feed the recovered reverb signal through a Drawmer DS201 in Duck mode , then use the main vocal into the side chain to control the reverb swell , with correct settings of the threshold attack/hold/release dials the reverb dynamically swells in the spaces between the vocal lines , the sound doesnt get crowded by the initial clang of the spring , nor do things become lost in a washy mess, it just leaves auditory vapour trails in the gaps .
The same Ducking type effect is also excellent with ambience mics on a drum kit , for instance using the toms on the trigger inputs .

Love those Drawmers - the go-to unit for all sorts of great effects. I remember recording an album in Byron Bay in ‘92 and on one track using low frequency sine wave generators tuned to a midi driven kick, but fed through a Drawmer triggered to open by the kick (plus other deep synth drums from an EMU Procussion) to create a sort of log drum effect - a bit like Taiko drums, I recorded everything to twin Studer A820’s sync’d together. Also the Indian chants at the beginning were originally recorded on wax cylinder in the 1920’s:

 

[Whoops]

common, standard, most used headphone cables
All unshielded

 

[RoadrunnerOZ]

Actually the oposite, normal headphones use 3 wires paralel to eachother not even twisted, 3 conductors, onde of the conductors is the return path connected to ground.
I fixed many headphone cables and I never ever seen a factory headphone cable with shield, it's always or 3 separate cables or 4 separate cables, unshielded.



I fixed today a cable of DT770 Pro headphones, and the cable is like I said above 3 conductors next to each-other, there's no shield in the DT770 cable.

Cool - so the ground wire is not a shield connection in a 3 wire - I always assumed it to connect internally to a shield. You learn something every day! I don’t service headphones - just the gear that drives them.

 

[Whoops]

Cool - so the ground wire is not a shield connection in a 3 wire - I always assumed it to connect internally to a shield. You learn something every day! I don’t service headphones - just the gear that drives them.

yes thats it. It seems the 3 wires (or 4 wires) are not even twisted, they seem to be physically parallel to each other like electricity power cables.

I just arrived home from fixing some DT700 for a friend, so I had to redo all the cable connections at both ends, new jack installed and new soldering to the speakers.

These headphones wires are really hard to solder, they are impregnated in varnish, so the solder doesn't stick into it.
You have to burn the varnish with a ligther, but be careful enough to not completely melt the copper. And then you hae to sand or scrap the burned varnish down in order to expose some copper.

I have no idea why do headphones use this type of varnish impregnated wires, I have no idea of the reason for it...

 

[RoadrunnerOZ]

yes thats it. It seems the 3 wires (or 4 wires) are not even twisted, they seem to be physically parallel to each other like electricity power cables.

I just arrived home from fixing some DT700 for a friend, so I had to redo all the cable connections at both ends, new jack installed and new soldering to the speakers.

These headphones wires are really hard to solder, they are impregnated in varnish, so the solder doesn't stick into it.
You have to burn the varnish with a ligther, but be careful enough to not completely melt the copper. And then you hae to sand or scrap the burned varnish down in order to expose some copper.

I have no idea why do headphones use this type of varnish impregnated wires, I have no idea of the reason for it...

It’s not varnish but some sort of enamel like varnish. Like in iPhone headphones - mine were always breaking at the plug end and I’d just cut the cable and solder a new TRRS plug on. The wire takes a lot of heat - from what I gathered from Apple (I used to manage a music store which was also an Apple Channel - we sold Apple for audio purposes) the coating is to strengthen the wire and allow routing of wires adjacent to each other that wouldn’t short out. I’d turn my iron temp right up and it seemed to do the trick - a bit like Litz wire - just feed the cut end of the wire into a hot blob of solder on a silicon mat and the coating burns off and tins the cable. Flame is a bit hit and miss - the burnt coating stops proper tinning of the wire or the wire just burns (nice green colour flame!). I got sick of my iPhone headset wires always breaking inside as replacement was too expensive. Seems like the toughening doesn’t work that well.

 

[Whoops]

the coating is to strengthen the wire and allow routing of wires adjacent to each other that wouldn’t short out.

Sure, but why not having a rubber coating like other audio cables instead of the enamel/varnish?

For example in the DT770 Pro, the wires have the enamel/varnish coating and then each has around it a normal rubber coating. I don't get it, if they put the rubber coating why having the enamel/varnish coating also?

 

[RoadrunnerOZ]

Sure, but why not having a rubber coating like other audio cables instead of the enamel/varnish?

For example in the DT770 Pro, the wires have the enamel/varnish coating and then each has around it a normal rubber coating. I don't get it, if they put the rubber coating why having the enamel/varnish coating also?

Maybe to prevent the cables shorting as I mentioned, once free of the rubber sleeve for termination, plus these wire strands are individually super thin and headphone cables go through a lot of continuous movement. Allows for tough skinny wire? Or to make you buy their replacement cables (or headset if it’s Apple)

 

[Newmarket]

Yes, if it says "designed for fixed installation" then it will be stiffer



I think so, I have to look into the Braid options

A spiral wound copper screen is usually more flexible than a braided screen.

 

[Tubetec]

Those coloured wires are bacially strands of fine magnet wire with kevlar fibres incorporated for extra strenght , its very robust yet flexible stuff , and insulated .
I often reuse strands of that wire where I want to reduce any chance of vibration , like where a tube socket is anti-vibration mounted with the rubber motor mounts , solid core wire would only transmit vibration . The litz wire attaching to the voice coil in speakers is also very handy in this regard , again good for making a vibration free connection to tube heaters where larger diameter cable is needed . I reclaim it from from broken speakers before I dispose of them .

The record you did still holds up great soundwise Roadrunner ,
and of course well ahead of its time on how were treating the planet .

I believe the 4 core mini starquad is commonly used in broadcast as headphone cable ,

 

[RoadrunnerOZ]

Those coloured wires are bacially strands of fine magnet wire with kevlar fibres incorporated for extra strenght , its very robust yet flexible stuff , and insulated .
I often reuse strands of that wire where I want to reduce any chance of vibration , like where a tube socket is anti-vibration mounted with the rubber motor mounts , solid core wire would only transmit vibration . The litz wire attaching to the voice coil in speakers is also very handy in this regard , again good for making a vibration free connection to tube heaters where larger diameter cable is needed . I reclaim it from from broken speakers before I dispose of them .

The record you did still holds up great soundwise Roadrunner ,
and of course well ahead of its time on how were treating the planet .

I believe the 4 core mini starquad is commonly used in broadcast as headphone cable ,

The lead-out wire is readily available cut and tinned if you or anyone need it - these guys do the super soft:
https://www.estron.dk/products/wires/https://www.estron.dk/products/wires/sf2-litz-lead-wires/Also they do the miniature cables as in hearing aids etc. The internal wire strands in the mini cables iare only 5 microns thick coated in polyurethane/polyamide enamel - I’m guessing that Apple use a similar material in their earphones.
I use fine Litz wire for repairing broken or rotted PCB traces - I used to get it on a cardboard reel but is readily available in various gauges in hanks or reels of differing lengths. The one I found best is the 32g - 34g single core for bending to and holding shape to PCB track paths and the 7 strand in various gauges for flexible connections. Teflon PTFE coating seems to handle the heat OK.

 

[gyraf]

..some types headphone cable is steel wire mixed with a little copper wires - meant to be crimped in, not soldered..

 

[RoadrunnerOZ]

Just pulled apart the DT770 Pro - the incoming cable is indeed a 4 core - no shield - but the RHS capsule feeder from LHS terminal strip where the incoming cable lands, going through the headband, is a shielded cable. Why is that?

 

[Whoops]

Just pulled apart the DT770 Pro - the incoming cable is indeed a 4 core - no shield -

In the ones I repaired the cable was a 3 core and not 4 core

but the RHS capsule feeder from LHS terminal strip where the incoming cable lands, going through the headband, is a shielded cable. Why is that?

Yes the small cable going from the Left Speaker to the right speaker in the headband is 1 conductor+Shield, like instrument cable.
I don't know the reason for that, I think they could have just a cable with 2 conductors side by side

 

[RoadrunnerOZ]

In the ones I repaired the cable was a 3 core and not 4 core



Yes the small cable going from the Left Speaker to the right speaker in the headband is 1 conductor+Shield, like instrument cable.
I don't know the reason for that, I think they could have just a cabe with 2 conductors side by side

One of my sets is really old, (the other set is new with 3 core - just had a look) the cable I believe had been replaced in the old ones by the people I got them from - (probably from some other model or a special order replacement - maybe they used to have that as an option??) They came from a recording studio I did some repairs for as part payment of a service bill (along with some other gear)
Weird about the shielded cable….