When using truly balanced interconnects, i.e., differential signals on pins 2 and 3 and ground on pin 1, Ive found its very often advantageous to float the ground at one end of the signal path. This can be easily done by disconnecting the ground on pin 1 at one end, and only one end, of the cable.
The result is that the cable is still shielded but there is no electrical connection between the chassis grounds of the equipment. This not only increases hum isolation but also prevents high frequency digital clocks and switching power supply noise from traveling between chassis.
Ive used this floating ground scheme on large analog post production installations (with lots of patch bays and signal routers) as well as on my AES/EBU balanced digital audio cables at home.
On a separate note, while balanced interconnects have way better noise immunity than unbalanced its not free: they require twice as much circuitry in the signal path and both sides of a balanced circuit must be perfectly matched.
The result is that the cable is still shielded but there is no electrical connection between the chassis grounds of the equipment. This not only increases hum isolation but also prevents high frequency digital clocks and switching power supply noise from traveling between chassis.
Ive used this floating ground scheme on large analog post production installations (with lots of patch bays and signal routers) as well as on my AES/EBU balanced digital audio cables at home.
On a separate note, while balanced interconnects have way better noise immunity than unbalanced its not free: they require twice as much circuitry in the signal path and both sides of a balanced circuit must be perfectly matched.