I have my stereo TV connected to an older Pioneer stereo amplifier. In the past few months, a low pitched hum has begun when watching (or, more accurately, listening to) the TV. This happens regardless of the program source (cable, VCR, DVD, or XBox).
The set up is like this: [cable --> VCR --> TV all with coaxial cables] [ VCR --> A/V switch --> TV --> amp (video input) --> speakers all with audio cables] [DVD --> A/V switch --> TV all with RCA cables] [XBox --> A/V switch --> TV all with RCA cables] [DVD --> amp (CD input) --> speakers with audio cable]
I hope the above makes sense.
Anyway, the hum only appears when listening to TV programs. It doesn’t happen when listening to CD’s or with the tuner (all using the same ampifier). It occurs to me that the hum could be an aging amp, but the hum is only when using the video setting of the amplifier. The amp is about fifteen years old.
Are there any cheap things (like cables) that could be causing this hum? I would rather not replace the amp if I don’t have to.
Big WAG here but could it be a groung loop problem? Is all of your equipment plugged into the same outlet / circuit on your house or could some of the equipment be grounding somewhere else? I’n not an expert on this - do a search on ‘ground loop’ for lots of info that may help.
I’ll look up ground loop. All of the components for the entire entertainment system is plugged into one plug strip (that is about 8 years old). That would be an easy thing to replace. Thanks.
I had this problem once and it was because ONE of my A/V items did not have a 3-prong plug, hence, no chassis ground. Any ways, what I did to prevent this was just ground all the equipment to a single point. I also had everything in two rack-mount units that aided to my goundloop problem.
I bought a spool of 20 gauge wire, some forked terminiators, or crimps. I loosened a screw on each item, slipped the end in, tightened. Then I just left a few feet of wire and cut it… did it to each componenent and found a place to ground everything too. I also relocated all the AC cables, as much as possible, away from any of the interconnect…
Also, make sure to look on the back of each item. Usually, especially on amp or recievers they will usually have a ground terminal or lug there already or a screw with a ground symbol next to it. Usually.
The ground shield on the female RCA jacks can break away from the circuit board from years of plugging & unplugging. This was in fact a common problem in Pioneer amps that I worked on. Do they wiggle as if they are loose? A continuity checker (if you have one) is the easiest way to see if everything that should be grounded, is grounded.
maybe the video input is simply crapping out on you. Have you tried plugging the video into the CD input? Have you plugged your sources one by one into the CD and video inputs to see if one of them produces the hum?
The way I understand it, you have all of your video sources plugged into an a/v switch and the a/v switch is plugged into the TV, and then the TV audio is plugged into the amp.
In addition you have the audio from your DVD player plugged into the CD input of your amp.
If this is the case, you can yank at least one of your connections.
You have cable into the VCR, and VCR into the TV via coax.
Then you have your VCR connected to an a/v switch, and the a/v switch connected to the TV. It sounds like you have your VCR going into the TV through two routes: the coax and the a/v switch. Since the audio from your VCR is already going to the TV from the coax, there’s no need to run another line from the VCR to the a/v switch. I don’t think this will fix your hum, but it will simplify your setup.
And last but not least, make sure the volume on your TV isn’t too high. For instance I have control over the volume coming out of the cable box, as well as volume coming out of the TV. If the TV is cranked but the volume on the cable box is muted or very low, there’s a residual hum coming from the TV. I try to keep the TV volume low and the cable volume high, and it results in a generally cleaner sound. Better for taping too.
In my years of video production in the field, many were the day when the Sound person would pull out a Humbucker ( so they were called ) to eliminate some pesky in-line audio hum. I spent a LOT of time Googling “Humbuckers”. I now know more about electric guitars than I EVER wanted to know, but I did eventually come up with this Audio Hum Elimination Site that might offer a reasonably priced solution to you.
Good luck ! I love my old tube Harman Kardon amp, and luckily haven’t had any big hum issues with it.
You understand correctly. I realize that this is a bit of an over-complicated setup, but it has its purposes. The VCR goes to the TV via two routes so as to simplify the cable input. Otherwise, I would have to split the cable with one leg going to the VCR and the other to the TV. I don’t rely on the coax VCR → TV connection because the stereo audio won’t travel that way – only mono.
The DVD is plugged into the CD input on the amp so that we can listen to audio CD’s without turning on the TV. Otherwise, the TV’s audio processor is required.
As Scotty said on Search for Spock, “The more you overtake the plumbing, the easier it is to stop up the drain.” I could simply have over-complicated my system. I’m going to work on this grounding problem. That sounds promising.
