Building balanced interconnects--ideas

FWIW, the whole idea behind balanced line cables was/is to make it so that the cable does not have an artifact- regardless of the cost of the cable.

To accomplish this there is actually a standard that has been in place for the last 60 years or so.

IOW, if you do it right you won't need particularly high-end materials like you do with RCAs.

With regards to the shield, if in doubt attach it to pin 1 at both ends of the cable.

Don't shield the wires separately. You want the twisted pair to have a common shield.

Jafreeman, the issue here is that if you put signal (ground) current through the shield, you can wind up with undesirable effects. In a balanced cable, the signal should only appear between pin2 (non-inverted) and pin3 (inverted) of the XLR. IOW ground should be ignored.

Quite often in high end audio the tenants of the paragraph above get ignored. The result is really expensive cables, or a lot of work put into the cables for no real benefit. If you run separate shields, you will loose a lot of the Common Mode Refection Ratio afforded at the input to the amplifier! IOW use a common shield- it will work better- noise gets into the cable, you **want** it to affect the inverted and non-inverted phases equally! If this does not happen the cable could well have more noise.

No. Use pin 1 for the shields of the cables.

Jafreeman, seems to me that you have a misunderstanding of what balanced operation is all about.

The origin of the technology was to reduce the effects of cable length; essentially, its introduction made transcontinental and inter-continental phone calls possible. The recording industry seized on the obvious benefits for audio- essentially this technology makes the cables sonically transparent, without having to resort to expensive executions.

It *is* possible to operate balanced line without a shield. To do this though, it is imperative that the receiving end be not just balanced, but also differential.

The bottom line here is that there should be no signal currents flowing through the shield- if there were, it would not be possible to set up a balanced line without one!

Now a lot of high end audio preamp manufacturers don't realize this. This will force you to have either a shield or at the very least a 'drain wire' to make the ground connection.

So if you want to avoid using a shield, then you will have to use a wire, similar to what your conductors are made of. Failing that, IOW if you plan to have no connection on pin 1 at all, your source **must** drive only pin 2 and 3, and must ignore ground. If you have an ARC, CJ or Aesthitix as examples, this simply will not work.

IOW if you 'don't want any metal at all,' as you put it, you will not be having a connection either.

My point here is also that there is no need to go through such an exercise- that was/is the whole point of balanced line operation, and exotic cable constructions do not improve on that unless something else in the mix is gravely wrong.