Ok, I found this expenation on
www.soundonsound.com. So now my question is since my E-MU has ballanced In's & Out's will I only benefit from this if my amp has ballanced In's, my guess is yes. Also, should I make ballanced interconnects if my amp does not have ballanced In's?
All audio signal cable is screened, which means that an outer conductor wraps around the other conductor(s) to shield them from electromagnetic interference. The outer screen, which may be made of wire braid, metal foil or conductive plastic, is usually connected to ground so that any induced currents (due to interference) flow directly to ground rather than being allowed to modulate the audio signal. However, screening isn't a perfect solution, which is why balancing was invented.
In an unbalanced cable, there's a single inner core that carries the signal while the outer screen also doubles as the signal return path. Any interference that results in induced currents flowing through the screen conductor will cause these currents to be added to the wanted signal, so some interference problems are still possible, especially with long cable lengths or where there are nearby sources of strong interference. Though it's not often realised, screened cable offers very little protection against induced hum, as the cable is actually acting like a single-turn transformer, coupling energy from other mains conductors and transformers in the vicinity.
For the long cable runs used in live rigs, it is not uncommon to find Star Quad cable in use. This is a screened cable with four individual internal conductors, two of which are used for each of the elements of the balanced signal.
In a balanced cable, there are two inner conductors, often known as hot and cold. The screen is grounded, as before, but this time the screen is not part of the signal path. More importantly, balanced equipment is designed so that its hot and cold outputs carry the same signal but with the cold signal phase inverted with respect to the hot signal. At the receiving end, the balanced input stage re-inverts the cold signal and adds it to the hot signal, thus restoring the original signal. The clever part is that any interference that makes it through the screen is likely to have virtually the same influence on the hot and the cold conductors (as they are in more or less the same place). As a phase reversal is implemented at the input of the receiving piece of equipment, any interference common to both conductors will cancel out. The effectiveness of this system depends, amongst other things, on how well balanced the hot and cold arms of the circuitry are at either end of the cable. Mic amps often have a specification for common mode rejection, which is a measure of how effectively the circuitry rejects interference that is common to both hot and cold inputs.
A further type of cable known as Star Quad was developed to further improve the immunity to interference, and this works by having two pairs of internal cables wired in parallel, but spaced (actually woven or plaited) so that any interference induced due to the cable cores not occupying exactly the same position in space is largely cancelled out. Star Quad seems to be used mainly in live sound applications where long cable runs are commonplace, but it is demonstrably more effective than conventional balanced cable.
I think this type of connection should be easy to create, just buy some mono 1/4 jacks and a switchcraft mini, but what has me confused is the ballanced/unballanced crap. Can someon explain the difference, and if I were to create a "ballanced" interconect what would I have to do different from creating an "un-ballanced" connection. Thanks!