how to get rid of hum


have conrad johnson premiere 140, hooked to v ray , hooked to seperate ac line and 2nd ac line hooker to front end with v ray and mbl transport , dac ,preamp , hum is at a low level does not increase as volume rises but yiou can here it on quiet passages annoying please help
pavpet
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Running a ground wire from the amp to the center screw on an AC outlet sometimes works. Using a cheater plug to float the ground also helps on occasion. This is a system dependent problem. Begin as Bob suggests by plugging in in various sequences and see if you can isolate the problem. AC is a funny thing , those of us with Nameki (sp)? direction finders know that systems sound better in one orientation than another. If you want to check this out for yourself and do not have one of the old fashion cheater plug [ a plug that takes a 3 prong plug down to 2 for you nubies] just grind down the bigger prongs on a current polarized cheater plug. The difference varies with every system but there is usually a considerable difference.
Could be a transformer hum in your C/J...Incoming power can cause this low level hum..I have it but its at a modest level and it changes..Usually worse in the winter..( more electrical load ) and hot summer days ( high ac use for air cond. ) I have learned to live with it...Though my hum is very modest and not that big a deal..But it is there.....
I have had 2 episodes with hum. Cable TV coaxial lines are notorious for carrying hum into a stereo system. Try disconnecting coax lines and see if this is the source of your hum. A small isolation transformer put in the coaxial cable eliminated this hum. Some components with 3 prong AC plugs can cause hum in my experience. If you can find the offending component then a cheater plug (one with 3 slots on one side and 2 spades on the other side) may do the trick. This happened to me with a turntable, the cheater plug eliminated the hum.
I am having the same problems with hum in my system. I've tried lifting the ground, but doesnt work.

"If you can find the offending component then a cheater plug (one with 3 slots on one side and 2 spades on the other side) may do the trick. This happened to me with a turntable, the cheater plug eliminated the hum." -Rfj5106
-was that one component responsible for all the hum in the system? i get hum without any interconnects to my amp...

"Cable TV coaxial lines are notorious for carrying hum into a stereo system. Try disconnecting coax lines and see if this is the source of your hum. A small isolation transformer put in the coaxial cable eliminated this hum."-Rfj5106
-my system is a 2 channel system... does this mean that the coax cable for my cable tv in the other room can cause hum in the ac lines even when my ground is lifted?
If the amp puts out a hum when all other components (except speakers) are disconnected, the problem is the amp. Turn the amp off before disconnecting, then turn it back on to check.

Breaking off the ground pin on a three-contact plug is not a good idea, and could even be lethal. Those are there for safety. If you have a "ground loop" making its way around through the power cords, it would be a lot safer to try to fix it by connecting all to the same outlet. Or better yet, get an isolation transformer.