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Looking for better results from the PX - Do I even need it?

klarkkentsterklarkkentster Posts: 14
edited August 2013 in DriveRack PX
Presonus 16.4.2
2 - QSC K-12's - Mono
1- Ksub

Overall - just not happy with the sound of the system. Does not sound full, lacks low end etc..etc.

Do I even need the PX with the SMAART features of the Presonus board and X-over in the QSC's ?

I read through the " Start Here" portion and the "Auto EQ" portion. I will go through and re- do the auto EQ portion 4-6 feet away from the speaker and see what the does.

Any thoughts or input would be greatly appreciated.

I also saw the suggestion of cranking up the Sub Gain all the way and then backing it down to blend with the other speakers - I will try that as well

Comments

  • GadgetGadget Posts: 4,915
    Hi,

    Not only do I have all the driveracks, but I also have the Presonus 16.4.2, and I'm also a moderator here, and @ Presonus .com. I LOVE them both!

    Yes, the QSC's have a crossover built in, but I prefer to use the driverack for this purpose. The reason? Well, the driverack has numerous crossover slops to experiment with, also it has PEQ's and GEq's, as well as numerous other tools you can use to perfect your sound.You can even experiment with different crossover points and find what works better for you, and your system.

    The Presonus mixer is an awesome piece of kit... However, the SMAART implementation is for taking the room affects out of the equation....What I do is tune the speaker system the best I can with the driverack, and then the room is neutralized much easier with the mixer's SMAART implementation.

    Perhaps you could tell us what you doing currently, including crossover points, gain / cut on the different crossover slopes, Equalization both PEQ and GEQ...Then maybe we can see what your problem is...

    G
  • The only thing I have done with the drive rack is gone through and utilized the QSC presets in the drive rack... I have not made any other adjustments.

    I then ran the SMAART.
  • GadgetGadget Posts: 4,915
    Well, maybe you should look at the presets for those speakers, or, better yet start from scratch and "roll your own..." . The process isn't difficult and you will have better results.

    The process is easy, just follow the wizard.

    You could modify the same preset also. Press the setup button and set the the crossover type to LR24, set the xover point at 118hz...both the HPF and the LPF. (the point where the subs and the tops cross...)

    Since you have only one sub I'm not surprised you are disappointed at the low end, but the clarity can be repaired by setting things up as above.

    Note that there are lots of helpful tips and tricks in the:

    Start here thread:
    viewtopic.php?f=61&t=959

    and the FAQ's
    viewforum.php?f=60
  • klarkkentsterklarkkentster Posts: 14
    edited August 2013
    Thank you. I will try that tomorrow.
  • Well - I tried it. I hit " Setup" went through and changed three settings to 118HZ and LR24. When I finished there wasn't any low end.. LED lights on sub out were non - existent. So i'm assuming I did something wrong.

    So - i couldn't get off the current setting for some reason..ended up powering off/on and going through the wizard again. I notice the speaker level setting was at 19% and Sub speaker level - 29%... not sure it matters...but I changed the speaker to 50% (matches the gain on the mains) and 60% on the sub (again matching the gain on the Sub) and it seamed to have a much better low end.

    I will try next week to adjust to the setting you have recommend,,,, but am I missing something on setting this thing up?


    Keep in mind... i have about 15 minutes every Sunday to mess with this... we are a portable church that sets up and tears down every Sunday
  • Gadget - just curious if you had any additional thoughts?


    Thank you in advance
  • GadgetGadget Posts: 4,915
    Alright, driverack 101, I don't have the PX in front of me but are you specifying a 4 way setup? In the DRPA PX line they consider a stereo tops and stereo subs a 4 way config, a two way would be stereo tops and a 3 way stereo tops and mono sub ( you would use the MONO low out)...

    So, if you speculated anything other than stereo 3 way or 4 way you would have NO separation of tops to bottoms.

    Just as an exercise, pick any 2 way preset, then load it and go into the crossover the Hi outs are used and you only get a HPF... set the HPF as low as it will go and play some fullrange CD's through the tops and sweep the crossover point up slowly and the low frequencies should start to disappear by the time you get to 100 hz and continue up till the midrange starts to disappear and only the HF should be present... in the K12's by the time you get to 2KHZ the only thing you should hear is the horn...

    Now select a a 4 way and set the HPF to 20hz and the LPF to out.. (unplug the tops...) now the subs should be putting out every frequency that they can... (up to 150hz)...Now start the same music and start turning the LPF down and the high( low mid actually) frequencies should diminish the lower the LPF goes till there is nothing but muffled low end ... conversely, if you reset the LPF and use the HPF, the higher it goes the less low end there should be...

    Try this and report back...
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