HELP: How to get rid of AC hums and video noise


Hello Audiogoners,

I need help from members of Audiogon more experienced than I am with AC HUMMMMMMMS!!!

My video system is pretty standard: a SACD/CD/DVD player, an audio/video processor, a 5-channel amplifier, 5 speakers and a self-powered subwoofer. Plus of course the various power conditioners & transformers. Oh, I forgot. there are also the VCR, cable box, S-video enhancers and all kinds of wall warts associated with them. Well, maybe the darn thing is not that simple but I still think it is a pretty typical video system.

Anyway, each time I made anything that amounts to more than a minor change in this video system, I have to spend a lot of time chasing down those AC gremlins such as hums in the speakers and/or dark bars moving across the TV screen. Floating and reversing polarity of various AC plugs in even such a standard video system can be very time-consuming and frustrating--i.e. not always successful.

Is there a systematic method to chase down or prevent those AC gremlins?

Or is there perhaps a hum eliminator(like the Ebtech for music equipment) made for RCA connectors?

Any help to alleviate this frustrating experience would be greatly appreciated. THANKS.
justin_time
Have you tried a ground loop isolator on the cable to your cable box? Oftentimes adding one to a system with TV cable attached will cure hum completely.
the hum and the dark bars are audio and video ground loops most likely due to the coax connection. Try detaching the CATV coax and see if it goes away. If it does,then get an isolation transformer as Rex said.
I had luck getting rid of a nasty hum by replacing the digital cable with an optical that connected the cable box and the AV reciever.
the TV Cable coax. First, the hum/lines disappear if I play the TV without the processor/amp. Second, the hum/lines are there when I play a DVD with the cable completely disconnected. So, it's got to be in the processor or multi-channel amp. But I tried everything with these pieces to no avail (Sigh!).

I guess I may have to disconnect everything and reconnect the system piece by piece, not something that I look forward to.
I can only repeat what is said above - Isolate the CATV-in from the rest of the system first.

I use the Jensen VRD-1FF, but I am sure there are others.

Once that is done, hook every component up to the same single electrical outlet.

If you still have hum, start connecting and disconnecting everything (both the electrical plugs and the cables) until you can find the source of the hum.
The cable box was the first thing I disconnected but, as I said before, that wasn't the problem as Rex and Swampmaker suggested.

Unfortunately, with all the high-power components in the system (amps, powered subwoofer, TV and several transformers/conditioners), it is not possible to hook everything to the same AC outlet as Riffer recommended without overloading it.

I guess I will have to find this gremlin the hard way: float everything except one common ground (processor) and check every single AC polarity for the lowest noise.

Any other options?

THANKS.
Every amp that has hummed in our house has stopped with the use of a cheater plug. The only other cause we've seen (we don't have cable TV) is power tubes being way out of bias.

Good luck.