Checking the AC polarity of your amplifier


What is the best (or easiest) way to check the AC polarity of your amplifier. Has anyone used the Van den hul with any success. What was your method?
foster_9
There have been instances where I preferred the higher leakage voltage. This also gets quite muddled with parallel transformers, such as Equi=Tech. Sometimes the leakage voltage is shocking (no pun intended).
Robbyg, Stuartbranson, Tbg:

Robbyg: The reason one makes the measurements with the component off, and all input/output connections detached is because what your trying to determine is how all the component's various circuits "grounds" combine and where that total is positioned electrically -- i.e is it closer to the "hot" blade of the power cord or the "neutral" blade of the power cord. Depending which way the blades of your equipment's power cord are oriented relative to the real "Hot" and "Neutral" of the electrical service in your wall, you'll get a bigger potential difference or "leak" in one position or the other. The position with the smallest leak will give you the least hum in your system when the component is finally turned on.

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Stuartbranson: You little devil!! Of course you could, but what about when you start to get oldtimers disease like me, and forget what you did where. Or what if someone buys your house and can't understand why they keep getting shocks from their vacuum cleaner!!

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Tbg: Soooo....you like a little electrical stimulation once in a while, do you?! "Higher leakage voltage" indeed! Listen: Audiophiles are a dying breed, so please be careful, we need you. If you find yourself craving higher and higher leakage voltages, please, email one of us before it's too late, your body fries your computer and you lose all contact with the outside world!

Neil
On some components with advanced power supply designs, "balanced power" will lower the performance quite noticeably. Before investing in such a device, you should check with the manufacturer of each component to find out if is suitable for use with such a device.

Here's a post i made about Noise, Hum and AC Polarity a few years ago. It may explain a few things to those that have questions or are confused about what to do. Sean
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Neil, as long as it is below 32 volts I am unconcerned. There also is little current.

Sean, while balanced power does seem like a great idea in reducing noise, I do think many crafty designers, assuming unbalances power, can result in users with balanced power having problems. I was one.
One of my friends was using a preamp that i was very familiar with. We discussed a few things over the phone and i told him that he had the polarity reversed on the preamp. I told him how to verify this and once he checked it, it was reversed as i had suspected.

After changing the polarity and listening for a while, he told me that he had never heard that big of a difference when playing with the AC on any component before. The reason why the differences were so obvious? This specific product has a built in noise trap / transformer damping circuit that requires specific polarization to work properly. Without the proper polarity OR using balanced power, that circuitry is completely negated and the preamp will never work or sound nearly as good as it can.

This is why i said that one should check with the manufacturer of the gear before investing big money in what could be a major step backwards in their AC systems. It is also the reason why i've touted high quality isolation transformers, as they will only strip away the noise without altering the polarity of the signal. Sean
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