tomiiv30 OP14 posts01-03-2019 12:00am@jea48
With my amp only one is buzzing, the left one, so lets say I do have dc on my ac line why would only one buzz? IMHO I think that the one that buzz is a bad one comparing to the right one which is a good one. It would be the only explanation.
So what I did was, I turned off every switch in the house except the on the amp is plugged in and yes the buzzing sound got quieter but was still present. But having an expensive amp that has much better transformer than a cheap amp this little interference when all breakers are on should do nothing to it.
I bet you that every house has the same problem when you have multiple things running in a house such as ac units, furnaces, washers and dryers etc, you can't tell me that there is going to be no interference at all, but this expensive amps should take care of that problem. - I could be wrong.
I agree, McIntosh should have incorporated a DC blocker circuit in the amplifier.
So what I did was, I turned off every switch in the house except the on the amp is plugged in and yes the buzzing sound got quieter but was still present. But having an expensive amp that has much better transformer than a cheap amp this little interference when all breakers are on should do nothing to it.The DC on the AC mains could/can be coming from a neighbors house that is fed from the same power company's utility power transformer as yours.
Just doing a quick Google search I found this manufacture of a DC blocker. You might give them a call and see if they can build you one to handle the power requirements of your amp. JMHO, the one shown is not big enough. Make sure you give them the AC power requirements info for the amp.
https://avahifi.com/products/humdinger-dc-line-blocker