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High Noise Floor

espruntesprunt Posts: 11
edited August 2007 in 200 Series General Discussion
I am using a DR260 to process a JBL VRX712M. The amps are QSC PL2 218 on highs and a PL2 236 on lows using the downloaded processor settings. There is a high noise floor on the high amp even when the 260 outputs are muted. If I unplug the output from the crossover all is quiet. Am I missing something?

FYI: I tryed an analog crossover and there still was a smaller noise floor but all went quiet when muted the crossover.

Comments

  • GadgetGadget Posts: 4,915
    Have you tried different setups? an all custom setup? Is the unit new? have you done a gain structuring? Have you swapped the output from the highs with one of the other 4 output channels? If you have tried everything else have you exported any settups you have to your computer (because a hard reset will wipe them) and done a HARD RESET? If all else fails contact tech support.

    Gadget
  • mix_jenkinsmix_jenkins Posts: 1
    I have the same problem with this noise floor. Unhook input signal noise is there. Unhook output signal to amps and noise is gone. This noise is there even with all outputs muted and no signal going in. It is a very annoying high frequency that just pierces the eardrum. Its not a loud signal. I've done all the above and a firmware flash. Any other ideas?
  • kpippenkpippen Posts: 551
    Hi Guys,

    Please excuse my stupidity...and I hope it's only a terminology thing...but would someone please explain what “noise floor� is?...

    There are several things that could introduce “noise� into a sound system… Some of the most common would be improper grounding…or a ground loop between two separate power sources… Or if speaker and low-level signal cables are ran together in parallel over distance…

    Kevin
  • DraDra Posts: 3,777
    Kevin, allow me... :D

    \"Noise floor\" is a relative term. It describes the amount of noise the room has naturally. In an empty room the \"floor\" is quite low. In a packed auditorium and people sitting quietly (breathes, whispers, seat sweaks, foot movement, etc) the \"floor\" is higher. If they are all conversing, higher still and if they are screaming for there favorite band, it is really high. A sound system only has to over come the \"noise floor\" to be effective, whether the \"floor\" is 30db or 100 db. A system for an opera house needs to be much quieter (noise wise) than for Quiet Riot, but not as much output needed.

    Mix, I assume, is talking about the noise his system is producing with no input. So, it appears your recs are in line.

    DRA
  • kpippenkpippen Posts: 551
    Hi Dra,

    The terminology \"noise floor\" definately makes sense to me as you've explained it...:)

    Personally I like \"floor noise\"...because it fits better I think... If it was called floor noise I wouldn't of asked the stupid question...:lol:

    It seems to me that noise floor could only enter a system through a sensitive omni-directional microphone and this entire thread is not even about noise floor...

    Am I missing something here?...

    Kevin
  • GadgetGadget Posts: 4,915
    Hi

    Dra.. nice...
    The original post is 6 months old and the poster never checked back in.. I suspect his .. and your problem stem from the gain structure.. or lack there of... The back of the manual or the \"Welcome please read before posting\" have that information in easy to follow steps.

    My 260 is dead quiet...I have my system up and at concert volume and there isn't anything till the system explodes into action...(unless of course the bands instruments are noisy)

    If you have done a gain structuring and still have this problem the more info you can give the better, including, equipment list, setup parameters, amp attenuator settings.. etc.
    Gadget
  • DraDra Posts: 3,777
    K, I think what he is implying is, his system (whatever component) is introducing (and therefore creating ) it's own noise floor / floor noise / chicken - egg / egg - chicken. Imagine this... you're mixing your son and his bandmates. Their output is averaging 90db, which is well above the \"noise noise\" of 60db (wherever it comes from). You now play a cd containing pink noise with an output of 80 db into their mix. Somewhere I have read there is a minimum db span from floor to system output for us to \"hear\" the content. IF that minimum where 15 db then the introduction of the pink noise would drop the span to only 10 db and while you could still hear it, it would be a strain. (Totally made up numbers)

    If I remember right, it was in (and surely lots of other places) THE YAMAHA SOUND REINFORCEMENTS HANDBOOK.

    Dra
  • kpippenkpippen Posts: 551
    Dra,

    Sooo...in other words....\"noise floor\" can be exactly as you described it...or any undesirable noise coming out of your system other than you intentionally put in...:)

    For me...\"rap\" would be considered as noise floor...:lol:

    On the other hand...\"floor noise\" is simple to overcome... Just CRANK IT UP!...8)

    Kev
  • DraDra Posts: 3,777
    Rock & roll :twisted:
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