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Audio Noise from my step up/down transformer

I just bought a 220V Pathos TT integrated amplifier and it came with a PowerBright Step up & Step down Transformer for use here in the USA.
I am hearing noise coming through the speakers that I think is coming from the step up transformer.
When putting my ear next to the transformer there is a noticable low hum and when listening to the noise in the speakers it has the same pitch as the transformer but is several octaves higher.
The noise is present in the speakers whether the volume is up or down although the noise gets noticably louder when turning the volume all the way up

Any thoughts?

Thank you
jetrexpro

Showing 1 response by shadorne

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shadorne
7,467 posts
 
You probably have a power imbalance and you are using too small of a transformer for the task. This causes transformer core saturation on either the positive or the negative AC cycles... leading to harmonic distortion and a DC offset that induces noisy ground loops which are easily picked up on RCA interconnects.

Your amp uses something like 240 Watts when run at 220 volts suggesting it will need around 500 watts at 110... so I would use at least a 1000 watt transformer to be on the safe side.
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