1. Join Now

    AVForums.com uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Hissing sound through speakers

Discussion in 'AV Receivers & Amplifiers' started by Mr Forgetful, Jun 7, 2004.

  1. Mr Forgetful

    Mr Forgetful
    Active Member

    Joined:
    Jun 7, 2004
    Messages:
    377
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    18
    Location:
    West Midlands
    Ratings:
    +15
    Hi, I have just bought a Denon 2200 DVD and Denon 2803 reciever with Monitor Audio Radius speakers, the sound is great when watching a DVD but when I listen to the TV through the reciever there appears to be a hissing sound. The audio leads are are connected from an output on the rear of my Sony TV to the TV input on the rear of the reciever, also I have a FreeView box and this is connected into the DBS input on the rear of the reciever but I get the hissing sound through this also.

    Any thoughts or remedies :lease:



    Dave
     
  2. dynamic turtle

    dynamic turtle
    Active Member

    Joined:
    Mar 23, 2004
    Messages:
    1,501
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    41
    Location:
    Central London
    Ratings:
    +17
    Sounds like a ground-loop problem. Had the same issues with the set-up in my bedroom after I added an active subwoofer - a constant background hiss through the speakers. I think its caused by having too many ungrounded componets. It will affect some functions more than others (my xbox, curiously, was unaffected by the problem). You can buy a groud-loop isolator from maplins (£10 - shark - designed for use in cars, but fine with home cinema IMO).

    Could be down to something else, but GLI's are useful (& cheap) things to have around.

    Test first by attaching a piece of bell-wire to the AM ariel loop clip (should have an inverted "fork" symbol next to it) and the other end to a screw in the back of your subwoofer/digibox/tv etc. If there is a noticeable drop in background hiss, you have a ground-loop.

    DT

    P.S. I accept no responsibility for electric shocks received as a result of this activity!!!!!!
     
  3. Mr Forgetful

    Mr Forgetful
    Active Member

    Joined:
    Jun 7, 2004
    Messages:
    377
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    18
    Location:
    West Midlands
    Ratings:
    +15
    Thank you for your reply, firstly, what is meant when you say an active subwoofer, I have a subwoofer with it's own power supply, is this what you mean?
    I do not have any ariels connected also as I don't ever intend to listen to the radio through the reciever (I bought a DAB/FM/MW tuner for my Hi-Fi), I will only be watching movies and trying to listen to the TV through this set up.

    What is a ground loop????



    Dave
     
  4. jeff-o

    jeff-o
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    An active subwoofer is one with its own power supply and amplifier, so yes, you have an active sub.

    The suggestion to short the AM ground to the case was simply a troubleshooting technique to help determine whether you have a ground loop. Don't worry, it's not permanent!

    A ground loop happens when points on a circuit which are supposed to be at equal potential (in this case, ground) are not. You then get small currents flowing between points where they shouldn't. These currents cause noise and other wacky things to happen.
     
  5. dynamic turtle

    dynamic turtle
    Active Member

    Joined:
    Mar 23, 2004
    Messages:
    1,501
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    41
    Location:
    Central London
    Ratings:
    +17
    Yep, Jeff-O is right, it is just a trouble-shooting technique! Another way round this could be to remove the co-axial lead and power cord from the sub and see if the "hissing" remains (as the sub has no connection to the mains, or to the receiver any more).

    If this doesn't solve the problem, try the wire technique described earlier between each component. Once again, because the receiver is the "hub" of your system, have one end of the bell-wire inserted into the AM clip and try attaching the other end to metallic parts of your other components. If the hiss is slightly reduced, or stops completely, its a ground-loop, baby! Get that GLI and use it between the "infected" components. Problem solved.

    BTW, nice kit you've got there. 2200 & MA Radius - groovy.

    DT
     
  6. Mr Forgetful

    Mr Forgetful
    Active Member

    Joined:
    Jun 7, 2004
    Messages:
    377
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    18
    Location:
    West Midlands
    Ratings:
    +15
    Cheers for all your advise guy's, I have phoned the store and they have given me ideas to source the problem ie connecting up other audio sources to see if there is hissing through them and I will be taking back the receiver for them to look at, if there is nothing wrong found with the receiver one of thier staff will come up and have a look at the set up and look also at the TV, if it's the TV audio output then for the time being I will have to listen to the TV through it's own speakers until my next lotto win!!
     

Share This Page

Loading...