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It gets worse. AC noise can cause intermodulation distortion (IM) that is unwanted spurious frequencies created between actual musical frequencies often not at harmonic ratios. The result is non-musical off-key distortion affecting imaging and signal accuracy. In addition to noise-inducing reactive currents, another issue affects power quality and ultimately sound – the power factor. When total power supplied to a load is greater than actual power used the difference is wasted as reactive power like previously discussed. The ratio between true and apparent power is called power factor. An ideal ratio is 1:1 but this is never the case with a typical impedance load inside an unbalanced power system. You end up with voltage and current out of phase relative to each other and as Martin states, "this shift in voltage away from the active current phase means that to that extent there simply is no power present. Voltage and current must be in phase for power to exist and for electricity to actively create an effect. Low power factor means that the efficiency of equipment power supplies is negatively affected.”
If you believe that your system sounds better at night it probably does. Industrial users on the grid during the day can exacerbate poor power factors. Martin contends that balanced power gives your system a fighting chance to sound just as good at three in the afternoon as it does at three in the morning. Finally if you want information—and also a lot of misinformation—about hum and power noise, search the forums for topics related to proper grounding. Equi=Tech’s position is simple. With reactive currents flowing into ground combined with the inherent copper resistance in our 12-gauge power distribution wiring and the resistance of a home’s external grounding rod, we end up with an unacceptable ground voltage due to Ohm’s Law.
Equi=Tech’s solution is to remove the noise at the source thus preventing it from getting into the preamp and the amp. The issue is that you never know which equipment or devices in your house are causing the problem. It could be the new Nintendo, a new television set with a different type of power supply, a computer or the washer motor cycling on and off. There is no way to deal with each one of these appliances at their individual source. The problem is far too large. Virtually every remedy including traditional power filters, conditioners, transformers, capacitors in the grounding circuits and even lifting the ground are mere band aids. None of them get to the root of the problem.
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We now get to the real beauty of balanced power. Remember that balanced power has two 60V mains legs that are mirror images and inversely phased to each other. The reactive currents flowing back through each of these 60V mains are also inversely phased mirror images which when meeting at the center tap common ground cancel each other out perfectly. You heard the term common mode rejection for balanced audio circuits and cables. This is how it works with balanced electric power too. It’s simple, elegant and almost foolproof. "There is never any voltage or current present on the ground reference in a balanced power system. Transient voltages and reactive currents which normally would appear on the neutral and ground wires are also out of phase and likewise sum to zero at the ground reference thereby canceling out AC hum and noise." Balanced power and balanced audio systems are conceptually identical. Both employ common mode rejection to eliminate noise. balanced power simply operates at higher amplitude.
Let's back up a little to "foolproof.” The system is foolproof assuming both sides are absolutely phase opposites for total cancellation. If tolerances are even slightly off you end up with narrower bandwidth of noise rejection. This is where Equi=Tech trumpets their superiority - the tolerances that Martin and his group claim are at the limits of current technology with the assertion that their patented transformer windings produce virtually perfect phase accuracy.
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Let's look at the same impedance load with the balance system in Figure 6. The reactive currents (in red) are canceled at the center tap for total elimination at the ground. Martin explains that "basically what has been done here is to redefine zero. Actively zero is now defined as the mean voltage differential of the AC sine wave. Reactively zero is defined as the sum of everything around it. And herein lies the magic between clean electronic circuit operation in a balanced power environment. Simply stated it works like this: by virtue of the equal presence of inversely phased reactive power elements on the ground, noise is eliminated. Ground is now a zero sum equation. There are no longer any stray potentials around to corrupt signal circuit operations." Simple, elegant and when implemented on all the audio equipment in your system, one can end up with up to 20dB better dynamic range.
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When you use electricity a dynamic event occurs. It is not just flipping a switch to convert energy to work in a one-sided equation. A very complex reaction takes place between power supplies, gain circuits and the AC power system each affecting the other. The load affects the power source and the power source affects the load and both affect the phase angle of the power. Add next into the mix high frequency contamination from solid-state devices. Since there is no perfect switch, moving transistors from on to off quickly produces a burst of frequencies that become accumulative in each piece of equipment. This garbage is running through the system on the ground between various devices. The result is either audible noise from the speakers, increased IM distortion and/or alterations of the sounds’ inherent characteristics. Furthermore power issues occur not merely as 60Hz hum. Spectrum analysis of the noise shows a variety of higher harmonic frequencies invading our systems.
The Equi=Tech system works in real time whenever you turn on your equipment. balanced power is a deliberate series of actions and reactions which with the 10WQ arrive at equilibrium within seconds. At that point when the incoming electrical power combines with system loads into equilibrium, you operate in state where harmful reactive currents and noise are canceled out and eliminated.
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Another positive effect is that current and voltage stay in sync. You cannot load down the relationship and ruin it. Martin and other balanced power advocates take a very simple position. They don't care where or why the noise originates or which way the power harmonics travel. It’s irrelevant. All that noise can be inverted, creating a mirrored out-of-phase version which can be nulled out with a very simple transformer. Martin humorously described the process for my non-scientific benefit as little Pac-Men running around the wires eating noise.
Now that we’ve been introduced to balanced power, let's move to the product itself, safety concerns, its future and most importantly the effect on my sound system
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