Try it just on the preamp.
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disconnect the interconnects from the preamp to the amp...no buzz? Disconnect everything to the preamp and reconnect the preamp to amp interconnects..buzz or not? If not, reconnect each source one at a time and see what causes the buzz. Most preamps to amps are going to have a small amount of white noise, especially tube preamp to SS amp.
You should not plug your amp into the Hum X is it is only rated at 6 amps and will restrict your power amp.
Have you tried changing the interconnects from your preamp to your amp? Sometimes a connection goes bad causing the hum. I found many years back a very good source of info on tracking down hum problems were some white papers on the Jensen transformer website.
If nothing else works you may have to change power conditioners. I have had good luck with several Furman conditioners but when I tried several other brands in my home theater system I got hum. Sometimes you just have to experiment.
Ok, here is where I am at. I have 4 sources plugged into my pre, a PS3, TV, Oppo HDMI and Oppo analog. I can leave the TV plugged in via HDMI, but I have to disconnect the HDMI for the PS3, Oppo HDMI and Oppo analog for the buzzing to go away. Does this mean the pre is bad or do I need new analog and HDMI cables? Thank you guys for all your help.
Call The Cable Company (www.fatwyre.com). They're very good with these type of problems. If they recommend something, they will let you try it first so you know if its the right thing for you. I've been using them for years and find them to be very honest. They should know exactly what to do for you.
You probably have a ground loop. If you disconnect the cable feed to the TV set and the hum drops away that would confirm it. A ground loop is caused when there's a difference in ground potential between your cable and electrical grounds. You can solve it by breaking the ground connection at either end. On the cable side you can use a pair of baluns 75 ohm to 300 ohm & 300 ohm to 75 ohm wired back to back to lift the ground there. Or use a 3 prong to 2 prong ground lifter on the electrical side to break the connection there. Also make sure the preamp is not stacked directly on top of the power amp as it may pick up induced hum from the power transformer.
@Kalbi23...BDP-105 settings insists on either hdmi or analog, you cannot have HDMI ticked in settings or your music will have an echo affect. You have to untick HDMI in settings when going from video to two channel audio. Oppo HDMI to the tv input, tv output for sound should be a toslink cable to avoid the ground loop. I run my toslink directly from the cable box instead of the tv. I will not use coax/rca from any video source to another source much less to the preamp because of the ground loop. With that said, I also keep the cable box and tv on a different circuit than my audio.
Ok, called fatwyre, and they were no help. Basically told me to call the electrician, I guess that is my last resort. I've disconnected everything that is on the same circuit and the cable from the wall, but the buzz/hum remains. The only way the buzz/hum disappears is when I disconnect all components from the pre. I do have my pre stacked on top of the amp, put it side by side instead and the buzz remains, is it still too close? I would have to buy new XLRs if I need it to be further apart. Any other thoughts or suggestions? Thanks again everyone.
I replaced the pre with another AV7701, the hum is still there. I called Marantz and the support rep said, my amp is faulty. I asked, when I use my Oppo as the pre, how come the hum isnt there? The rep had no explanation. I went back to my store and asked if I could borrow a different pre, borrowed the AV8801. No noise what so ever from the speakers. Does this mean the AV7701 has a internal grounding issue? Thoughts? Thanks for all your help to everyone.