Testing Audio Output

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  • tech2014
    Badcaps Veteran
    • Aug 2014
    • 807
    • Canada

    #1

    Testing Audio Output

    I have a Harmon/Kardon AVR-630 with a sound problem. I found the service manual and it goes through a setup to put a signal in the 6/8 channel direct input, then measure output at the pre-out. It says to set the volume to -40 to -25db and measure the voltage on the scope. What should a good level be coming out of the pre out. What would a good peak to peak voltage be?

    See pics below. Top one is the input, bottom pick is the output level I am seeing on the scope on the pre-out, with volume set to -10DB. Is this too low?

    Click image for larger version

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    Click image for larger version

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    Shouldn't the output be higher
  • Longbow
    Badcaps Veteran
    • Jun 2011
    • 623
    • USA

    #2
    Re: Testing Audio Output

    You are making the problem more complex than it needs to be and confusing everyone with your description of the setup. What exactly do you mean by "a sound problem"? A typical amplifier input level is near 1v p-p max. This is a monster processor so keep it simple. You will need the owner's manual and the remote. I'll bet one of the surround settings has been tweaked and you will find it about 5 levels down on the menu. Try a factory reset if they tell you how. Its much faster and will cure lots of problems in some cases.
    Is it plugged in?

    Comment

    • keeney123
      Lauren
      • Sep 2014
      • 2536
      • United States

      #3
      Re: Testing Audio Output

      Yes, always do the simple things first. Yes, your output should be higher then your input. If you find that the factory reset and other things do not correct your problem. Then you will need to state exactly what problem you are experiencing, like no sound out of speakers or one speaker etc., what type of set up do you have when this problem occurs, like is this happening only at certain times with certain equipment. Once people understand what is happening then schematics, service manual and test equipment maybe needed. First though do the factory reset as Longbow suggest.

      Comment

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