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Need help for Headroom meters

giusfregiusfre Posts: 28
edited March 2012 in PA General Discussion
Hi! I have red everything about this on this forum but I haven't found an answer to my problem!
I have set my mixer output (Mackie Onyx 1640) for a correct gain structure (as per DRPA+ instruction and for all of this forum posts) to a 0 db (+ 4 dB switch both on the mixer and on the DRPA+) with a pink noise running on a free channel:only the 30 imput headroom meter led lights is on!?
If i set the mixer out to +7dB (the last position before clipping) only the 30 imput headroom meter led lights is on!
In the output section only the sig led light of the meters is on on the low and the 20 light is on on the mid/hight!
No limiter! No compressor! No eq! Only the crossover is set to separate low (100 Hz) to mid/Hight!
If I switch the DRPA+ to -10 dB imput only the 20 imput headroom meter lights!
In effect my speakers (2 x 750Watt mid/Hight + 2 x 1.000 Watt Subwoofer...a total of 3.500 Watt!!!) absolutely don't seem to work at their own power.
If i send the signal directly from the mixer to the speakers the level seems to be too loud!

- At what level should the imput meters be with an appropiate output from the mixer of 0 dB or at a maximum output of + 7 dB?
- Is there any way to increase the signal level on the DRPA+?
- At what level should the DRPA+ output meters be to send a correct level to the speakers?
- Did I have to increase the output gain in the crossover section to increase the output level of the DRPA+ to have a correct level to the speakers?
- Have my DRPA+ some problem or is normal to have this very low level on the imput and output level meters?

Many thanks for the help and sorry for my bad english!

Comments

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    DraDra Posts: 3,777
    Did you buy this unit used? If so it could be that the internal jumpers have been changed to show a different reading on the meters.

    The x-over gains will not increase the input meters or level on the outputs.

    DRA
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    giusfregiusfre Posts: 28
    Dra wrote:
    Did you buy this unit used? If so it could be that the internal jumpers have been changed to show a different reading on the meters.

    The x-over gains will not increase the input meters or level on the outputs.

    DRA

    thanks for the answer and help...

    No! The unit was new. How can I control if the internal jumpers are ok (i don't really know where to find and what they are)? Do you find that the level of the meter is too low or it is normal to have this kind of level?
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    DraDra Posts: 3,777
    The default setting is as it should be. DO NOT open the unit. It will void the warranty. Assuming that you have in fact NOT engaged a compressor (input side) the meter should match the mixer meter's. You may have a dud. Return it to the retailer.

    DRA

    PS - Are you using the EXACT same cables (and no adaptors) between the mixer and DRPA+ as you used from the mixer straight to the amps?
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    GadgetGadget Posts: 4,915
    Without getting into a whole discussion of meter ballistics lets just say that they are far slower than the actual event, in this case a peak sound. The fact that the increments are -SIG, -30, -20, -10, -3, and -0- should tell you that there is 10dB between the majority of the meter elements (that are already not fast enough to catch the peaks). These two factors combine to make the meters (on both your devices...) pretty useless.

    What were looking to do here (and there are gain controls on the driverack, they are on the crossover/filters) is get the system all talking the same language (volume). It's less important here to worry about inacurate visual representations, than to get the signals on the analog devices (mixer and amps) to peak together. This is really the only meaningful thing here, other than NOT clipping the Driverack.

    So, take the signal in the mixer to just below clipping (so that the peak light on the main outputs is just flickering) [ ...*note* if you can't get them to clip add channel gain...] With the master meters on the mixer JUST clipping, and the speakers disconnected, get the amps to JUST clip as well...(remember this is the point we want to NEVER exceed) this tells us that the mixer and amps are at the same point...now, to insure that the mixer clips before the amps (this gives us a visual representation that the system is maxed out) turn the amps down 3-6 dB (even 10 or 12dB is a good number).

    This would of course be the amp on the speakers that are LESS loud, the other, will need to be turned down to match outputs..

    Don't worry about the meters on the Driverack...use the gains on the crossover/filters to add gain for the amps if necessary.
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    DraDra Posts: 3,777
    Not to be contrary 8) , but if using pink noise, then getting within 6 db would be pretty easy (meter to meter). I know I have NO issues matching pink noise levels and even playback is pretty close. He is +7 db on the mixer and - 30 db on the DRPA (37 db difference :shock: ). Combine that with the fact that when removing the DRPA from the loop the system is way loud.... kind of confirms a level problem at the DRPA's input or a cable "oddity" before the DRPA.

    DRA
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    giusfregiusfre Posts: 28
    Dra wrote:
    The default setting is as it should be. DO NOT open the unit. It will void the warranty. Assuming that you have in fact NOT engaged a compressor (input side) the meter should match the mixer meter's. You may have a dud. Return it to the retailer.

    DRA

    PS - Are you using the EXACT same cables (and no adaptors) between the mixer and DRPA+ as you used from the mixer straight to the amps?

    No! I use 2 x Vovox xlr/xlr 1mt. Cable from mixer to drpa+ and 2 x cordial xlr/xlr 10 mt. Cables from mixer to the self powered speakers (rcf nx m15-a and rcf 4pro8003-as) that are the same that i normally use from drpa+ outs to speakers! The vovox cables should be much better than the others...
    So you mean that the imput meters should light up completly with a +7 dB signal from the mixer? And what about the output meters?
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    DraDra Posts: 3,777
    You should get a solid illumination of the -0- LED on the DR. If you haven't moved the x-over gains, then the output meters should "roughly" match the inputs.

    Whatever cables you used to go direct from the mixer to the speakers (when it got really loud) are the cable that you need to use when you go from the mixer to the DR. You don't even need to connect the speakers for this. You are just checking the cables to see if you can now more closely match the meters.

    DRA
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    GadgetGadget Posts: 4,915
    giusfre wrote:
    So you mean that the imput meters should light up completly with a +7 dB signal from the mixer? And what about the output meters?

    Dra Wrote:
    You should get a solid illumination of the -0- LED on the DR. If you haven't moved the x-over gains, then the output meters should "roughly" match the inputs.

    Ummm... I have to disagree...I'm not sure what Dra was responding to, but a +7 signal from the Mackie mixer should NOT provide a -0- or full scale reading on the driverack! The driverack has a max input level without clipping of +20 dBu, the mixer is rated at max output of +21dBu... so, full scale just about clipping the meters on the Onyx should be just clipping the Driverack...
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    giusfregiusfre Posts: 28
    Gadget wrote:
    giusfre wrote:
    So you mean that the imput meters should light up completly with a +7 dB signal from the mixer? And what about the output meters?

    Dra Wrote:
    You should get a solid illumination of the -0- LED on the DR. If you haven't moved the x-over gains, then the output meters should "roughly" match the inputs.

    Ummm... I have to disagree...I'm not sure what Dra was responding to, but a +7 signal from the Mackie mixer should NOT provide a -0- or full scale reading on the driverack! The driverack has a max input level without clipping of +20 dBu, the mixer is rated at max output of +21dBu... so, full scale just about clipping the meters on the Onyx should be just clipping the Driverack...

    Problably i should not have a full scale lighting in the imput meters but the thing that i think is sure is that a only one or two led lights on on the Dr with a full scale output from the mixer isn't correct! Same thing for the output meters: i can't think that only the "sig" led light is on with a full scale signal (+ 7dB)
    There must be something that don't work!
    I have done a hard reset of the drpa+, done a completely new preset for my powerd speakers, no compression, no limiter, no eq...only crossover frequency for the subwoofer, tested all the cables...nothing! Alwais the same thingh...it not seems to be a cables problem!
    I had the suspect when, last week, i had my new speakers, that are double powered than the previous one, but i obtain quite the same overall max volume with a full range output signal from the mixer... This was suspect! I should have had a lauder volume!

    It seems that the dr have a problem with the imput signal...but my suspect is also that i'm doing somethin wrong!
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    DraDra Posts: 3,777
    Gadget wrote:
    giusfre wrote:
    So you mean that the imput meters should light up completly with a +7 dB signal from the mixer? And what about the output meters?

    Dra Wrote:
    You should get a solid illumination of the -0- LED on the DR. If you haven't moved the x-over gains, then the output meters should "roughly" match the inputs.

    Ummm... I have to disagree...I'm not sure what Dra was responding to, but a +7 signal from the Mackie mixer should NOT provide a -0- or full scale reading on the driverack! The driverack has a max input level without clipping of +20 dBu, the mixer is rated at max output of +21dBu... so, full scale just about clipping the meters on the Onyx should be just clipping the Driverack...


    We must talking about different things. If the mixer is pegged, the DR shouldn't be at the lowest LED.

    DRA
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    GadgetGadget Posts: 4,915
    Agreed Dra, I was just answering giusfre that a +7 signal from the mixer should NOT produce a full scale reading on the driverack.

    I have always found that the meters on the driverack read low compared to what is coming out of the mixers...As I stated a full scale reading (pink noise with a crest factor of 6dB) should be +21dBu (from the mixer) and should provide a near -0- full scale reading on the driverack, but I suspect it would not...I suspect that it would read the average of the signal... or be tickling the -3dB led...

    giusfre, I too suspect you have something else going on here...have you verified that the crossover/filter gain is at -0-? Have you tried increasing that gain to see how much you have to add to equal the output of the mixer?

    Something here has me wondering though... the output of most modern mixers is typically +28dbu, a full 7dB hotter than the mixer discussed here. I wonder out loud if we added 7-8dB of gain if that would make enough difference to be about equal to the mixer> speaker sound.

    I would ask you to make SURE that you haven't got ANY limiters or comps on, I can't tell you how many times we have had an issue like this where the OP found that in fact the limiter was on, or the comp was on, or AGC was on...
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    giusfregiusfre Posts: 28
    Gadget wrote:
    Agreed Dra, I was just answering giusfre that a +7 signal from the mixer should NOT produce a full scale reading on the driverack.

    I have always found that the meters on the driverack read low compared to what is coming out of the mixers...As I stated a full scale reading (pink noise with a crest factor of 6dB) should be +21dBu (from the mixer) and should provide a near -0- full scale reading on the driverack, but I suspect it would not...I suspect that it would read the average of the signal... or be tickling the -3dB led...

    giusfre, I too suspect you have something else going on here...have you verified that the crossover/filter gain is at -0-? Have you tried increasing that gain to see how much you have to add to equal the output of the mixer?

    The crossower filter is set to -0-! I have to add about 6/7 dB to the output gain to equal the output of the mixer...more for the low...

    Something here has me wondering though... the output of most modern mixers is typically +28dbu, a full 7dB hotter than the mixer discussed here. I wonder out loud if we added 7-8dB of gain if that would make enough difference to be about equal to the mixer> speaker sound.

    I would ask you to make SURE that you haven't got ANY limiters or comps on, I can't tell you how many times we have had an issue like this where the OP found that in fact the limiter was on, or the comp was on, or AGC was on...

    Yes, i know what you mean. This was the first thing I have checked...no limiter, no compressor!
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