Actually the spec for XLR cables is their characteristic impedance, which is 110 ohms for digital XLRs but can vary for analog XLRs. Characteristic impedance is the impedance presented by an infinitely long length of a uniform transmission line. A cable terminated with a load equal to the characteristic impedance will transfer all the energy to the load without any back reflections, which is crucial in digital signal transmission to minimize reflections and resultant jitter.
Digital and Analogue XLR Cables - Is There a Difference?
After swapping both around for many years the only difference I've been able to hear is that analogue sounded better than digital when used as an analogue cable but maybe that was because I was using a digital XLR because one of my analogue XLR cables had gone down. Not very scientific. The Digital cost much less too.
Is there a special conductor used for digital XLR? Both are 110 0hms.
A pair of Analogue XLR can cost the same as one Digital XLR.
I'd really like a definitive answer. THX!