Balanced Interconnects??


Hello, What exactly are balanced vs unbalanced interconnects? I'm looking at some of Audioquests new line of interconnects, particularly the coral, to use as an interconnect between my Rotel integrated amp and CD player. Some of their cables are double balanced and others like the coral are triple balanced.Should these cables be used for special applications or equipment? Any info you guys could provide would be greatly appreciated. My System: Rotel RA-985BX integrated amplifier Musical Concepts modified CD player Vandersteen 2ce Signatures Audioquest type-4 speaker cable 15ft true biwire Shitty Radio Shack interconnects (soon to be replaced) Va
chris_pisani
Balanced connections on XLR jacks can send both sides, positive and negative, of the waveform. RCA connections can send only one side, usually the positive. So balanced stereo stuff has four signals to work with instead of two, and why it costs more when it's for real. This creates the possibility to correct errors (noise and distortion) before they reach your speakers. If you have balanced connections use them, otherwise don't worry about it. Btw, Hosa makes a nice 20 AWG microphone cable with Neutrik XLR's - about $30 per 20 foot pair on sale at music stores. You'll be laughing all the way past the stereo shoppe :-)
Single ended (RCA) cables carry the entire waveform, not just the + or - side of the signal. A balanced (XLR) cable carries the + half on one conductor and the - half on another. This allows for some small reduction in noise picked up by longer cables in that the + and - halves of the signal can be compared and any common noise between them can be summed (cancelled) at the input of the next component. This also applies to a "fully balanced" component. This is only true if the next component's input uses both halves of the signal. On some components where throwing in some XLR jacks is an afterthought, they simply use one leg of the signal. Components can also be balanced. If not, a splitter has to be used to output a balanced signal. My experience is that balanced sounds better on some components and single ended better on others. If you use long interconnects, some small reduction in noise is also possible.
Sorry Pisani, the waveform analogy is wrong. Per the Belden Cable catalog: A balanced line is a cable having two conductors which carry voltages opposite in polarity and equal in magnitude with respect to ground. If any audio signal is composed of both of these polarities, and don't ask me why that is, the RCA connection having only one conductor and one ground usually carries only the positive polarity portion of the signal. It simply cannot carry both at once.
The Parasound 3500 amp has the capability to use RCA single ended connects and run either positive, negative or both for a balanced single ended operation. However Rock is right, it takes 2 cables to be balanced this way. Your preamp or CD player would also have to have both pos. and neg. RCA jacks. Or you could do it the easy way and use XLR connects :-)
Your balanced cable description is correct, Rockvirgo; however, your description of single-ended cables is wrong. Just before a balanced output the entire waveform is physically split into two voltages, opposite in polarity and equal in magnitude with respect to ground. A single-ended output simply sends the entire waveform through one conductor and a ground. You don't need to carry each half on a separate conductor unless you want to benefit from "common mode rejection", afforded by balanced transfer of the signal.