Low buzzing through speaks


Hello All,

 

Need some serious help here. So I just (upgraded?) from a Marantz AV8802A to a McIntosh MX122 preamp. I also just got brand new Revel Performa3 speaks all around (5 channel setup). I disconnect everything from the Marantz and then into the McIntosh, connect the speaks and I have a faint buzzing through all 5 speakers (that was not there previously). I have everything plugged into a Furman Elite 20pfi power conditioner which is plugged into a dedicated 20 amp circuit. My power amp is a Simaudio Titan HT200 5 channel. This is not going through the Furman but directly into the other outlet on the same 20 amp line. I even tried plugging the Sim amp into the Furman to see if that helped-no change faint buzz is still there. I have unplugged just about everything, and the buzz is still there. It is very faint and does not get louder when I turn up the volume. Again it is faint and you have to put your ear up to the speaks to hear but it is definitely there. I have tried so many things and nothing gets rid of it. It is not my cable box (I did have that issue previously with the Marantz but as soon as I unplugged the coax from the box it went away so I just bought a coax loop eliminator connected the cable to that and noise was all gone) as I unplugged that and started there.

 

Any help would be so sincerely appreciated????

kingbr

Just wondering...am I correct in understanding that when all XLR’s are unplugged between the Sim and Mac, there is no buzzing? If that is the case, if you reconnect just 1 of the 5 XLR cables, does the buzzing return? If so, in all speakers?

Just for the heck of it, I would also trying connecting the grounds on the rear, between the the Sim and Mac (with any piece of wire you have laying around), and see if that changes anything. Try this with and without the XLR's connected. 

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Thanks for replying @dpop and great call. I thought of disconnecting the XLR cables 1 by 1. Have not tried that. But yes when I disconnected the XLR's between the Mac and my amp (everything else was connected at this point to the Mac and all the speaker cables to the amp), the buzzing was gone. My cables are Transparent Plus XLR's and they are under 2 years old so I figured it could not be the cables (and again taking into account the buzz was not there with my previous processor). But what else do I have to lose at this point? I will give that a shot. Again thank you for taking the time to respond and help😀

I see that both the Sim and Mac have 3 prong AC plugs. I don't think anyone has suggested it yet, but another suggestion is to temporarily (just for test purposes) lift a ground on one of the units (either the Sim or Mac), with the XLR connectors connected, and listen for the buzz. You can accomplish this by using a 3 prong to 2 prong AC adapter (hopefully you have one laying around, otherwise Home Depot or any hardware store has them). For this test, the only two units connected (with any inputs or outputs connected) should be the Sim and Mac, and nothing else. 

I actually tried the Hum-X which essentially is the same as using a cheater plug. It didn’t work, still had the him. Whilst I didn’t try the cheater plug specially, the fact that the Hum-X didn’t work leads me to believe the cheater wouldn’t have any effect. 
 

How would I connect a wire between the grounds on the amp and Mac? I don’t really see anywhere on either to connect a wire?