Mcintosh 250 Transformer Hum Normal

I had not noticed till today as it was very quiet here, I notice a slight hun from the unit, Nothing from the speakers.

Again I do not recall it but I had never had it on in a very quiet room and you have to be very very close (like right next to it) it could be that i just have very good hearing in that frequency range ;-)

If this is not normal what could cause it? The unit does not run warm and sounds great.
Hi Escorial, you could ask a shop to borrow a dc blocker for power amps and see if it helps... This could reduce or eliminate the hum and even improve sound quality, should dc on the ac line be indeed the problem
Problem is not the wiring, have a Macintosh 6100 here also,  that is dead quiet even if you put your ear right to the cabinet.

Its the 250 transformer Im sure and annoying as heck.

I have it in my bedroom and like listening at low levels through the night. I can hear this at over 12' away.

The dealer gave it a 30 day warranty,  sadly to say its going back. Its a  beautiful example but ...

Back to the Dc blockers, its not the AC here. I have other receivers and and some tube stuff and nothing make a hum like this.

House was rewired less then 8 years ago.

This amp would be great for a loud environment but not good for my application , plus these products are supposed to be quiet. So there is something going on and perhaps on the way out.

I did check to see if the mounts were loose and nope that was not the issue.

Its either the transformer going or something else causing the transformer to act up but at this point itys under warranty and Im not screwing with it anymore

Thanks all

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