Setting gain within the dbpx

jamminforever · February 2012

Wanted to get some feedback and suggestions with regards to equipment that we're currently using. I have studied the gain structure and all pertinent info, but this question is really posed with respect to a rather unorthodox manner in which we're running our PA. Due to the fact that we've upgraded and STILL need to upgrade further, but as most of you know, PA stuff isn't cheap, esp if you want a decent sound....

Anyways, here goes.....

We're running 2 Yamaha BR15 tops, and 1 QSC KW181 as the sub. (need to get one more sub) as the mains..
Our mixer is a Mackie 1402VLZ Pro.
We are using a Yamaha EMX512sc POWERED mixer strictly as a power amp, just to power the tops. ( http://www.sweetwater.com/store/detail/EMX512SC)

So, the 2 mains are coming out the Mackie and directly into the dbx-px. From there, one line goes to the sub. The other 2 to the Yamaha emx512sc to power the 2 BR15 mains.

The QSC is already powered, so no external power amp for that. With respect to what we have, how would you recommend setting the gain structure for the following 3 speakers ( 2 tops and 1 main ). I know that most people disconnect the speakers from the power amp and turn the 2 gain knobs on power amp to adjust the gain within the drive rack short of yellowing out and avoiding clipping. Since the yamaha emx512sc has a main master volume and we have the 2 tops plugged in to the 9-10 and 11-12 channels, how would I set the gain? Also, how should I set the gain with a powered sub such as the QSC kw181 that we have? Am I missing a setting in the dbx-px that I can turn up? When we rehearse and are trying out the system, the LED levels on the DBX barely register, MAYBE just light up the bottom green lights. I've got a feeling that we are not using the equipment that we have to max potential...

Gadget · February 2012

Hello again...

I guess you have the bug...too

You think you have it bad? I have just gotten the latest update to the Presonus mixer family... they added 31 band Eq's to all the aux mixes last month, and then, earlier this month, they added an app that allows all the auxes to be controlled by an Iphone, Ipad or Ipad touch... which means that if every member of the band (up to 10) can control their own mix! It's called the "Wheel of me"! and in the next month or so they are adding SMAART measurement to the mixer interface. So, we will be able to view spectral data right with the GEQ's!

Oh, and I have been mixing remotely with my laptop (or Iad, or Iphone)... no longer tied to the mixer! What a RUSH!

Ok, back to your questions...

Well, gain structure for is going to be pretty basic, crank everything up and see which is loudest and turn that one down to match the other...Yes there are gains on the driverack, but they are XOVER gains. You didn't read the START HERE" thread did you...The gain structure says that you should send a pink noise signal through the mixer, set the outputs so that the mixer masters are JUST clipping, and make sure the driverack ISN'T, if so then everything is FINE... Note that the meter increments on the inputs of the driverack are about 20dB apart...or more on the bottom 6 dB is a relative doubling of sound so 20 dB is HUGE!

Your badly under powered so be careful.
Gadget

Dra · February 2012

I would think that setting the gain on the Yamaha board amp would be really easy. Assumming that the amp is "matched" to the output of the mixer, then simply use the output meters as your clip light and don't hit the red.

DRA

Gadget · February 2012

True that... even has an input clip indicator if you use a channel...

jamminforever · February 2012

I did do a bit a reading on the start here thread, and even copied it down to a txt format for me to use. That really helped me understand what it entails, but the question was in retrospect to the rather unorthodox method that we have to power the speakers and in using what we have, to get the most out of. In other words, thanks to the start here stuff, I understand what to do, but with our equipment and the driverack, HOW to do it. It would be easily understandable, if I had one mixer, and one power amp for the tops, but I'm using that yamaha emx512sc for now.

As for setting the gain structure, in step 10 of the setting the gain structure, it is mentioned that it's for the DRPA, but I know that I can follow this for the drpx so I will try it out.

As for the equipment, all the stuff is at the drummers house, so due to my insane work schedule, I basically get one day a week to work with the equipment and even then, we have a ton of songs that we go over, so not a whole lotta time to play around. Will have to get some time to go over early and work with it.

Gadget · February 2012

Send the signal to the driverack...

Set the PX to a most any powered sub and top config.

set the PX to an HPF of OUT this allows the sub to set it's own lowest frequency and let the sub handle the limiting as well...(lower the HPF)

set the HPF/LPF of the tops subs to 118 LR24

Run the hi outs of the PX into 2 channels of the mixer amp, set the controls of the EQ to NOT affect the sound (-0-)... (unplug the speakers) with the mixer outputs at just about clipping...set the channels on the mixer to just below clipping as well (no clip light) set the master volume control so that the mixer starts to hit the last LED set (there may be a 2 color LED I don't know, but if so until the LED's clip, then back down a bit)

Now the mixer amp is set, you'll have to do a manual balance from here as in the start here thread (turn down the louder source...

G

jamminforever · February 2012

Thanks for your reply!

Gadget · February 2012

Oh, and I forgot, if you were to want stereo, then pan the source channels. :arrow:

Setting gain within the dbpx

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