Audio Research Refernce 75se

The noise isn’t transferring to the speakers from what I heard.

cant hear it from where I sit. But 1-1.5 meter away I can.

It is NOT normal BUT…how do you know the buzz can be traced to the ref75se? Could be the pre, the power, the source, the turntable, the refigerator, the phono stage. Was the system fully balanced and wired with xlr cables? Were they using xlr to rca adapters at the ref75se? You dont have enough data yet.

System was really high end all around . @ghasley 

you can hear the noise clearly coming out of the amp

its small buzz/hum , even can say sound a bit metallic .

Probably why the party in question wants to sell it. ARC is subject to as many problems as any other brand but cost x times more to repair.  No practical experience, just my impression to what is written here.  

Next someone who has had no problems will chime in and say otherwise, and that's ok.

@mike30 what I was getting at is that you dont have enough data. Ive owned this amp on multiple occasions, it shouldnt have noise. What power treatment were they using? Was the amp plugged into the wall? What about the circuit? What kind of power cable? Is it a dedicated or shared circuit? Shared power strip with switched mode devices?

you really should utilize the dealer channel. You think it will cost you more but it will save you money in the long run.