Axiom Home Page Forums General Discussion Technical Questions Is this normal

I have been using my new EPIC 80/350 for a couple of weeks now. I noticed that all my speakers make a certain "buzzzzzzzzzzzz" sound when I pause the movies. I don't know if this is normal or not? What could caus this? If not, is there anything I can do about it? Thanks in advance for your advices.

Nope, its not normal. It could be a ground loop. I don't have any experience here, so I will let someone more knowledgable answer further.

Syl, is this noise only present when movies are paused by you? Is it present during pauses inherent in music or in the movie sound other than when you specifically pause it? A ground loop hum/buzz would be audible during quiet moments in all source materials. If it's only during a paused movie, it would seem that the player is at fault.

Syl, how loud is the sound, and how close are you when you notice it? Most speakers will have a very soft buzzing (or power) sound when the receiver is turned on, however, you usually have to be pretty close (1ft or less) to hear it, it would not be audible from the seated position.

A ground loop buzz is pretty audible. If you think of how a tranformer on a power pole sounds, buzzzzzzz/hummmmmmmmm, if your close to one, that is what is sounds like.

To defeat, try to move your wire bundle around while you can hear the buzz. If it changes, its a ground loop. I had a Sony DVD that caused a loop in my system. Once I isolated the cable, then excluded the cable as the problem, the DVD player was the only option. Replaced it, and no more buzz. Also, old wires that have cracked due to many un/plug cycles can make noise.

In short, make the sound, and unplug equip until it goes away. Start with the cable line (the most notorious cause). If it is the cause, you can buy a solution from Axiom or others. Sometimes, just rearranging the wires can fix it.

From what I hear, it is probably a ground loop. The buzz is indeed very loud. I can clearly ear it from the seating position wich is on average 8 to 10 feets from the speakers. If it is ground loop, is it normal to ear thissound in each of my speakers? Finally, the cables used were a little long and I decided to roll them together instead of cutting them. I figured I could use this extra lenght if I ever decide to moove the speakers. I guess I should cut the cables to the right lenght and make sure there is no loop in them. Thanks for your help. I'll kepp you posted.

Hi SylBer,

It's almost certainly a ground-loop hum, and you'll hear it in all the speakers plus the subwoofer. Here's my guide to eliminating the hum with links to devices that will help you get rid of it:

http://www.axiomaudio.com/tips_eliminate_hum.html

Disconnect the cable-TV feed (or satellite-TV feed) from the cable box or satellite box and see if the hum goes away. It does not matter whether the box is turned on or off.

Regards,
Alan

this is absolutly not normal,
there is a open loop ground on the electrical circuit, i had few yesr ago the same problem, after a long investigation, we found that it was a ground problem on my HOME ELECTRICAL CIRCUIT !!!
, so i can suggest you before blame your equipment, check your home circuit. (by deduction, plug it elsewhere on the home).

Thanks Alan for the link. Chevy, I am not blaming the equipement and it will be difficult to blame my electrician, he is my father. I'll try to follow the advices in Alan's paper and see what happens. Also, I live right next to you in Magog. If you agree to send me a private message with your telephone number, I could call you sometimes for advices?

Hi,

Sure, and as Chevy pointed out, ground-loop hum can originate from a combination of factors. In my own case, with an EP500, I was able to eliminate the ground loop buzz by using an AC outlet that was on an entirely different electrical circuit than my AV receiver, TV, DVD player, cable box, etc. Sometimes the reverse of that will work--connecting all the components to a power strip so they are on the same circuit. But in my experience, about 90% of ground-loop buzz complaints originate with the cable-TV feed.

Years ago, I once fixed a ground loop hum for a reviewer acquaintance but I had to run a separate ground wire from the chassis of his McIntosh power amplifier to a cold-water pipe under the basement/bar sink. He used to have a show on CBC-Radio (English network) called "Gilmour's Albums". I cite that to show the various solutions that sometimes work.

All ground-loop problems are solvable--it just takes some careful detective work.

Alan

Hi,

I unplugged the cable-TV feed and the hum stopped. I have a power bar and all my components are on the same circuit. The bar is equipped with an entry and an exit for cable-TV. I'll try passing the TV signal through the bar to see if it makes a difference or not. Else, I guess I'll have to buy a video ground isolator.

I forgot to mention that there are three outlets called "transformer spaced outlets" on the powerbar in addition to an entry and exit for cable-TV. Not knowing what these were, I decided to plug all my components in the other "regular" outlets when I installed my HT. Could using one of these outlets for the sub be a solution to my ground loop problem? Thanks again for your much appreciated help.

Run the cable through the power bar inlet/oulet, I know of a few people that have had their ground loop issues resolved with this simple solution.

"Transformer spaced outlets" are just outlets with extra space between them for AC/DC transformers, aka wall warts.

Sigh. No room for Bumblebee then...

I had the same thing with the cable and bought the Axiom ground isolator. It worked like a charm, no more hum.

I had a ground loop hum with my ep500 caused by my TV cable. I had to purchase the axiom ground isolator to solve the problem. No problems ever since.