Transformers humimg........again

Pbnaudio,

The BPT 3.5 Signature ac isolator is a balanced power transformer unit. It is good for 2400Va / 20 amps FLA at 120V.
http://www.6moons.com/audioreviews/bpt2/flagship.html

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Shawnlh,

Now the important part, ALL components that utilize a transformer (BPT, Naim, REL's) all have transformer hum. And yes, it is transformer hum, NOT sound from the speakers.
Shawnlh

First off all transformers hum to some degree, some more than others, that is normal. Now if you can hear them while seated in your listening chair that is not normal.

Tried many other outlets in the house, with and without the BPT unit. No difference, all transformers still humming, whether alone or not.

Jmho that rules out DC on the mains. Had you said with a piece of equipment plugged into the BPT the transformer of the piece was quieter but the BPT was noisy, then I could have considered DC on the mains as a possibility. An isolation transformer will not pass DC from the primary winding to the secondary winding. A piece of audio equipment plugged into the BPT output would not be affected by DC on the mains feeding the primary winding of the BPT toroid transformer.

I see you live in Canada. I believe your generating and distribution power system is the same as here in the US.

Just a few things your electrician friend should check. Have him check the mains voltage at the main service electrical panel. Make sure the voltage is the normal voltage for your area.. Have him check hot L1 to hot L2.

Then check hot L1 to neutral, and then hot L2 to neutral. The two readings should be within a couple of volts of one another.
The combined voltage of L1 to neutral + L2 to neutral should equal the L1 to L2 voltage reading.

Next thing he needs to check is the Hz. It should be 60Hz possibly 59Hz.

Next have him check the voltage at the receptacle the audio equipment plugs into unload, nothing powered up, then check the voltage again with everything powered up. The voltage should not vary more than a couple volts.

As for an overhead electrical service, there is nothing wrong with them imo.

I assume the service feeding your home is single phase 120/240V nominal.

Post back your findings
.

Thanks Pbnaudio, your reply is copied, pasted, and printed. I will have electrician buddy check these points. I will report back.

Thanks muchly :)

Shawn,

Jim (jea48) is the author of the post above, he is always very knowledgable and informative about matters as your current perdicerment ( pun intended / or not 😄)

Jim points out that you already have balanced power from you power conditioner, so one question comes to mind do all your components transformers hum if plugged in by them selves or as a whole, if as a whole one of your components may have a faulty power supply which cause the other components transformers to hum.

Best of luck

Peter

Look around (no longer made) for a PS Audio Humbuster III...I found one and it works.

My experience is with toroidal transformers only. They're the circular ones. I had the same problem - hum coming from my amplifier's transformer (toroidal Plitron). Got an AVA HumDinger, hum is gone. Cost ~$125. I don't have any affiliation, and I don't sell anything.