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Excess pink noise all the time

shandit66shandit66 Posts: 6
edited February 2008 in PA Connectivity
I've got a DriveRack PA that I'll hooked up in my new house after being in storage for a year.

After running through all the setup and diagnostics, I still get a lot of pink noise coming through: all channels, all frequecy ranges.

I've tried swapping amps and disconnecting components.
With only the DRPA hooked up and nothing else, the problem has been isolated. Hooking the amps directly to the preamp fixes it.

So it seems that the DriveRack is creating the issue.

Does anyone have suggestions on what I could do? Help is greatfully appreciated.




  • GadgetGadget Posts: 4,915
    Well, by pink noise do you mean \"FM inter station like noise\" Or that which you get when you go into the wizard and actually do a Auto EQ pass, or are you simply hearing a little hiss?

    If the former, try a \"hard reset\" and see if the software just became corrupt...

  • This happens after the pink test. :)
    Its a constant background hiss.

    Sorry, how do you do a hard reset?

  • kpippenkpippen Posts: 551
    shandit66 wrote:
    Sorry, how do you do a hard reset?
    It's in the manual...:D
  • Ok - I did the reset, but it made no difference.
    Still lots of hiss across the entire spectrum.

    - Playing with the gain at different cross over points
    - swapped around a few amps
    - disconnected all inputs

    = no change.

    Its definately coming from the DRPA

    I noticed the same problem in a few other threads, but no solution, other than \"poor gain structures\"

    I circumvented the PA and straight from the preamp, everything sounds great. I compared the outputs of the Preamp and the DRPA on my multi-meter, and they're very close. So I don't think the DRPA is providing excessive gains.

    I'm no closer to a solution with this unit.

  • GadgetGadget Posts: 4,915
    There is an inherent hiss in the DRPA... that is a fact, when I was using high efficiency horn loaded full range speakers, it was evident.. When I went to a biamped speaker it was easier to mask with the gain on the horn, the powered cabs are fairly quiet , but it's still there...

    Thats all I have to offer, try hitting the amps with a lower output from the DRPA (Crossover gain) and see what happens
  • Fanman20Fanman20 Posts: 223
    What about earthing /cabiling issues
    Could be interpreted as pink noise
  • Gadget - I am used a high efficiency tweeter, but can also hear it through the mid range, just not as loud. Nothing through the sub. For the correct levels I have the tweeters turn down about 7.2 db. Mid has no gain, bass very slight gain.

    I've tried changing the gain, all the way up and down, but it doesn't make any difference at all. Just sounds like constant background noise.

    Cabling was the first thing I played with. Disconnected everything except the DRPA and the amps, then messed with all the settings. Again its a constant hiss.

    Some of the other posts suggest using the 480 model instead. Thats a large jump in price and I'm more likely to try the Behringer DCX2496. I'd loose the RTA, but I can work around that.
  • DraDra Posts: 3,777
    You said you already did the Auto-EQ. Are any (or a lot) of bands pegged? Are you using the compressor? If so, turn it OFF.

  • GadgetGadget Posts: 4,915
    I hear the 2496 is noisy as well.. why not send the unit in and get it fixed... sounds like it might have a problem...DBX is good, and fast in the repair DEPT...

    Make sure it's ALL the hi and mid outs...if it's not and just on one channel see if cable swaps on the outputs follow he noise, as Fanman said verify the cables, and try and see if there is a ground loop somewhere... You'll need to probably disconnect EVERYTHING from the DRPA connect up one known good cable ... probably to the quiet sub amp connect a horn to it's output and see if there is noise, if not try each cable on that known channel than follow with every amp and every amp channel then every output on the DRPA. Add cables/amps one at a time to see where the buzz comes in...if it's the DRPA send it in, but make sure you HAVE a problem with that and not a ground loop, or bad amp feeding back into the DRPA
  • Compression is off.
    After AutoEQ, the adjustments were all under -/+6 db.
    Its on both channels.

    I'm guessing the something is pooched and dropped it off at the local DBX rep for service. Hope they can do something with it. In all other respects, it has been a good unit.

    The one thing I did notice, is that after running it for a while, the unit does get quite warm. I gave it more ventilation but the unit itself seems to be generating heat - seems a little strange to me
  • Fanman20Fanman20 Posts: 223
    Looking forward to what your local DBX rep finds.
  • Reviving this thread because I have the same issue, though with a Driverack 260. Any solutions?

  • hex21hex21 Posts: 1


    Has anyone managed to solve the problem? I have the same problem ...
    I can't imagine dbx doing this this way, especially seeing the technical parameters.


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