AV Receiver dB Display

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  • 05-28-2005, 10:31 AM
    Walt B
    AV Receiver dB Display
    I purchased and just cranked up a Panasonic AV Receiver SA-XR70. All works quite well except I'm baffled because when increasing the volume (on the unit or with the remote), the dB display decreases in numerical value. The inverse is true: when decreasing the volume, the dB display increases in numerical value.
    Panasonic Customer Support said that is how the engineers designed the receiver, because they also asked the same question.. Apparently, I'm not the first consumer to ask and wonder why Panasonic would do such a thing. Can anyone offer an explanation as to why the dB display on the SA-XR70 operates in this manner?
  • 05-28-2005, 10:54 AM
    bjornb17
    its the same way on the harman kardon receiver that i have.

    the way harman kardon manual expains it is like this:

    if you leave all the trebble and bass controls in the neutral position, the receiver will be putting out its rated power when the volume display shows 0 db. when you lower to volue, it will probably have a negative sign in front. so when you descrease the volume 10 db, it will say -10db.

    They do this, just so you have an indication of how many db you have it below the maximum that the receiver is rated for
  • 05-28-2005, 11:07 AM
    E-Stat
    Quote:

    Originally Posted by Walt B
    I All works quite well except I'm baffled because when increasing the volume (on the unit or with the remote), the dB display decreases in numerical value.

    Unless you have equipment like the band Spinal Tap that goes to 11 :D, all output meters and LED ladders operate this way. It is expressed as a function of attenuation.

    rw
  • 05-28-2005, 03:58 PM
    GMichael
    Uht Oh
    I guess I must be driving my Yamaha into the clipping zone. When listening to 2.0 on pure dirrect I often go above zero. At times I've been to +10dB. Very loud!
  • 05-28-2005, 04:30 PM
    bjornb17
    Quote:

    Originally Posted by GMichael
    I guess I must be driving my Yamaha into the clipping zone. When listening to 2.0 on pure dirrect I often go above zero. At times I've been to +10dB. Very loud!

    you may want to avoid doing that if you want either of the following to last:
    a) speakers
    b) amplifier
    c) your hearing

    do your speakers have poor efficiency or what?

    anyway, keep it at 0 or below to be safe :)
  • 05-28-2005, 04:38 PM
    GMichael
    My Infinty Primus 360's are rated at 93dB. Don't know how close that it to reality though. I guess it's a good thing that I mostly use my system fot HT. It rarely gets set above -14dB for that. Usually it ends up being set below -20. I just get a little caried away when listening to music.
  • 05-28-2005, 07:15 PM
    Walt B
    Thanks To All
    Thanks for all of the input; it makes sense now. It would be helpful if Panasonic and other manufacturers mentioned in their manuals the things that all of you pointed out; I'll leave alone thoughts about so-called Customer Support. All the more reason for forums like this one.
    Well, next is to mount the movie screen and order some Tripp Lites.
    Thanks again.
  • 05-28-2005, 07:19 PM
    bjornb17
    you're welcome :)

    also, welcome to the forums, there are a lot of really knowledgeable people here (i don't consider myself one of them) that can help you with any kind of problem you have :)
  • 05-28-2005, 07:36 PM
    E-Stat
    Quote:

    Originally Posted by GMichael
    I guess I must be driving my Yamaha into the clipping zone. When listening to 2.0 on pure dirrect I often go above zero. At times I've been to +10dB. Very loud!

    Unfortunately, the fixed display indicates the attenuation level of the preamp stage. So depending upon the output of the source, you may or may not be clipping the amp. Like a conventional gain control, the relative position doesn't tell the whole story.

    It is for that reason I prefer output meters or LED ladders on the power amp which would tell you whether or not you were clipping. You should be able to determine, however, if you are clipping a solid state amp by the rapid increase in distortion. I am constantly amused by those who seem to enjoy constantly clipping their car stereos. The poor amps sound like they are gargling.

    rw
  • 05-28-2005, 07:41 PM
    bjornb17
    Quote:

    Originally Posted by E-Stat
    I am constantly amused by those who seem to enjoy constantly clipping their car stereos. The poor amps sound like they are gargling.

    rw

    yeah no kidding, i hear a bunch of cars driving by who's sound systems sound like a whoopee-cushion.