First let me say I think the 3.5 is one of the top power conditioners out there. Second, I have run several different power amps through my 3.5 signature and I thought it was beneficial. More black backgrounds, definitely lowers the noise floor.
But, yes, I experienced hum during certain times of the day or night when it is dealing with dirty power. The level of hum varied with how dirty the incoming power was and therefore how hard it was working. When humming, it was audible from the listening position about 12 feet, but only if no music was playing. With music playing it was too low in level to hear. And, just to be clear, often times there was no audible hum. I had another balanced pc before the BPT and it hummed all the time and sometimes could be heard during quiet passages. I bought the BPT to replace it and there was simply no comparison.
It is an excellent product.
Chuck
But, yes, I experienced hum during certain times of the day or night when it is dealing with dirty power. The level of hum varied with how dirty the incoming power was and therefore how hard it was working. When humming, it was audible from the listening position about 12 feet, but only if no music was playing. With music playing it was too low in level to hear. And, just to be clear, often times there was no audible hum. I had another balanced pc before the BPT and it hummed all the time and sometimes could be heard during quiet passages. I bought the BPT to replace it and there was simply no comparison.
It is an excellent product.
Chuck