Balanced Audio Signaling
I would like to offer a thought in this topic. It is about balanced signaling in quality stereo audio systems. Let us look at the most fundamental aspect of what is going on here.
1 – Audio signaling using electricity requires two conduction paths; it is an Alternating Current signal. This suggests that two independent signals (such as stereo audio) will require 4 independent paths or conductors to go from source to load.
2 In ‘single-end’ or unbalanced signaling one of each of the two signals is combined into a Common Signal that we euphemistically call “Ground”. In effect 4 wires become 3 wires, two signals and a ground. This Ground Signal is really (-Left)+(-Right). These signals are commingled into one new signal. In the case of a chassis ground all signals plus the power supply power supply are commingled.
I humorously borrowed a word from Quantum Mechanics that fits this in a way, I call it “signal entanglement”. (-Left) and (-Right) are ineffably encoded together as a new Transverse Electro Magnetic (TEM) Wave , guided physically through space-time along the conductor and through the dielectric. This is the physical form of the audio data.
The individual signals split back out of the common conductor based on the presence of the other half of the signal which is out of phase. Can we say opposites attract here? Yea, kind of – but that is another discussion. For now all we care about is that they split apart
I am confident of this because I have tested the phenomena in my lab and you do it all the time when listening.
One more thought before I get to the conclusion.
We as a community tend to agree that cabling affects the subjective performance of an audio system. For this to be true the TEM wave has to subtly change in flight. It is distorted by its flight from source to load through the connecting cable. This new signal is not distorted the same way as the other two signals, i.e. individual +Left+ and +Right. The geometry of space-time is different for the ground and the signal.
This signal “difference” is defined as CUB, Capacitance UnBalance and it is a distortion like ground pumping in single ended systems. Our “ground” stays the same potential (we fixed that problem with balanced), but the offset amplitudes on BOTH sides of the virtual ground are changed by CUB tolerances. The advantage is we ISOLATE the SIGNALS from the rest of the system’s variations.
If the differential signal is magically perfectly separated by the opposite signal at the end, what happens to the difference in the signals? Mother Nature doesn’t like this kind of crap, that energy has to go somewhere.
Energy that can’t be used is REFLECTED until it is attenuated or atrophied out. T he line impedance change due to CUB causes irregular TEM properties. The transfer function loses information. CUB is that confusion as it varies down the cable. CUB is the BULK to ground difference in percent but the underlying issue is IRREGULAR TEM properties of the transmission line. It can’t be perfect.
This is a form of Entropy. If so then we are experiencing Information Entropy. Confusion (distortion) that alters the information.
Ouch, sounds like the way you can describe a cable sounding.
So what is Balanced about? Try Sonic Information Entropy Reduction where less is better.