[steinba]

A friend of mine came up with this idea, that I thought was brilliant. ...But really simple, so I wondered if somebody had already tried it. Seems probable.

The idea was to recable a pair of headphones for balanced operation, and terminating the cable with two TRS connectors. The connectors would be wired with the L+ signal to the tip on the left channel connector, and the R+ to the ring on the right channel connector. The minus signal would be wired to the sleeve on both connectors.

This way, an ordinary stereo jack Y-splitter would work as an adapter for single ended use.

Of course, the balanced amp would have output TRS jacks wired the same way, and it would (as always) be essential to not mix up the left and right channels.

What do you think? Has anyone tried this?

 

[MASantos]

If you use the search function you will find numerous threads about this subject!!! There are some balanced amps out there, balanced replacement cables for phones !!!!!

 

[taylor]

I agree that it would work fine for personal use, but there are just enough XLR balanced amps and cans that it would be difficult to get everyone to change to it.

While on the subject of simplifiying balancing, why is it that they people use all sorts of transformers and stuff to get the inverted signal, when they could just use a simple op-amp based amp, setting the gain to unity and putting the signal in the inverted input on the opamp, i.e.

SE source > unity gain noninverting opamp > amp > +
> unity gain inverting opamp > amp > -

Then you could have a switch on the amp for the - to switch between the output from the inverting opamp and a second set of SE inputs, so you could have two separate cans running from two separate sources in the same amp, which would be useful for meets and such.

 

[Garbz]

The problem with the opamp idea has been discussed in detail between me RickCr42 and AMB and a few others in the thread discussing transformers.

Opamps are an acceptable way to do this, but would rely on absolutly perfectly matched transistors to get the signal balanced equally. Some Balanced Line Drviers like the DRV134 has these opamps with laser trimmed resistors but introduce phase distortion since one signal travels through an extra amp. Transformers have none of these problems, decouple the grounds on both sides, but have the disadvantage of being big heavy expensive and like everything leaving their own signature on the sound.

It's really down to personal taste. I used opamps, I switched to BLDs which worked well, and then I used transformers which I like the best. Btw a 4pdt switch and you can bypass the transformer too.

 

[taylor]

double post.

I submitted it, got one of those error pages, so I hit back and my text was still in the box, so I ate dinner and did some stuff then came back and hit submit.

 

[steinba]

Quote:

Originally Posted by MASantos If you use the search function you will find numerous threads about this subject!!! There are some balanced amps out there, balanced replacement cables for phones !!!!!

Of course I know that balanced headphones are nothing new. I was referring to the two TRS connector and Y-splitter "hack" for an easy way to swap between balanced and single ended modes on the headphones.

 

[steinba]

Quote:

Originally Posted by taylor I agree that it would work fine for personal use, but there are just enough XLR balanced amps and cans that it would be difficult to get everyone to change to it.

I agree, but if one was to build an amp, and recable his own headphones, while still having a cheap and simple way to use the headphones with ordinary, single ended systems, I thought this would be an elegant solution. (Of course, whipping up a 1xTRS-to-2xXLR adapter cable wouldn't be THAT difficult either, but still...)

Do you really think there's enough commercial balanced headphone amps available using XLR output connectors yet, to call it a standard? How many can there be? A handful, maybe? The headphones that come with balanced cabling and XLR connectors surely are special/boutique items, and most of the time ust a standard headphone with an aftermarket cable, right?

...Anyway, that's beside my point. I just thought the idea was good. I wasn't really trying to change the way today's amps are built, or anything. I'll leave it at that.

 

[ChickenScrtchBoy]

i don't see the appeal if you have headphones worthy of a balanced set up, why would you be using an off the shelf TRS splitter? since you are making the adapter yourself (you are recabling the headphones, so it's not much stretch), you might as well just do the normal XLR hook up or a dual mono connection...

 

[steinba]

Quote:

Originally Posted by ChickenScrtchBoy i don't see the appeal if you have headphones worthy of a balanced set up, why would you be using an off the shelf TRS splitter? since you are making the adapter yourself (you are recabling the headphones, so it's not much stretch), you might as well just do the normal XLR hook up or a dual mono connection...

I follow you. I also think I agree. Still think it was a nice little trick, though.