decibel output confusion

ronaldo141
ronaldo141 Posts: 41
edited February 2003 in Electronics
my denon avr 1803's volume control goes from -60-18. The manual claims this is in decibels, but obviously this cannot be right. How can i measure how many decibels the receiver is really putting out? Is this the purpose of an SPL meter?
Post edited by ronaldo141 on

Comments

  • HBombToo
    HBombToo Posts: 5,256
    edited February 2003
    You got it Friend.

    There are quite a few variables tied up in what you have perceived as loudness.

    Go to the Shack.

    HBomb
    ***WAREMTAE***
  • goingganzo
    goingganzo Posts: 2,793
    edited February 2003
    on my recever i have a choice between relitave and apslute. reletave is -60 -- +something. i have never turned mine past -20 what the number means it is 20 dp down form referance levels. i think...
  • ronaldo141
    ronaldo141 Posts: 41
    edited February 2003
    but if negative numbers mean the volume is a certain amount below the reference level, then what do positive numbers indicate?
  • Dr. Spec
    Dr. Spec Posts: 3,780
    edited February 2003
    Originally posted by ronaldo141
    but if negative numbers mean the volume is a certain amount below the reference level, then what do positive numbers indicate?

    Above reference level.

    Some volume controls are rated that way - they can be set to "0" at any relative setting - anything below zero is negative, and above zero is positive, but the overall range of available increments doesn't change.

    Only way to determine true reference level is with a calibration disc like Video Essentials or AVIA. The VE requires 75 dB on the test ones, and AVIA requires 85 dB. Whatever master volume setting gives you this is approximately "reference" for DVD playback.

    Before you go trying it, be aware that most systems cannot play at reference level; the sub being the limiting factor. It is also uncomfortably loud. Try 10-15 dB below reference to start and se how you and your system like it.

    The increments on the volume control are relative; -40 would be 10 dB louder than -50, etc. That's assuming your volume control really is rated in dB increments.

    BTW, a 10 dB increase is perceived as being twice as loud. A 3 dB increase requires twice as much input power.
    "What we do in life echoes in eternity"

    Ed Mullen (emullen@svsound.com)
    Director - Technology and Customer Service
    SVS