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PEQ question with EAW subs

MaxxarcadeMaxxarcade Posts: 12
edited December 2012 in PA Configuration Wizard
I'm a bit confused with the settings listed here:

http://www.eaw.com/info/EAW/Processor_S ... ttings.pdf

I'm using the SB180. There is no mention of Shelf settings, so I'm not sure how this would translate to actual config on the PEQ of the DRPA+. Do they just want a 5db boost at the center frequency of 30Hz?


On a side note, room cancellations are a pain! I have 6 of these subs in a 15x20 basement room, stacked on their sides 2 wide by 3 high, with the tops on either side. Standing 6 feet away, there isn't much bass, but in the next room, things are bouncing around like crazy. I really need to get some acoustic treatment if it ever becomes affordable.

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    GadgetGadget Posts: 4,915
    Shelf settings??? Assuming you have "ultimate" power for the subs (at least 2X the program power for the tops...) set the Xover @ 80hz BW24, If you have LESS power, raise the Crossover point correspondingly...

    The HPF for the subs is 20 hz (LOL) BW 24...you better have MASSIVE power available.. and there ain't NO way those subs will do 20hz...

    Personally I don't like setting the crossover point on top of the kick drum 1st harmonic...I'd raise it up, to 90-118hz BW18 and be done with it...We also find that the LR24 transition point between top and subs to be very symmetric and pleasing sonically.. the LR24 slope has a 360 degree phase differential that just sounds more musical...
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    DraDra Posts: 3,777
    Apparently the +5db boost at 30hz makes them do 20hz.
    The Shelf or Bell parametrics are selected.

    Bell: All bell
    Low shelf: Shelf on the low side and 2 bells on the high.
    High shelf: Shelf on the high side and 2 bells on the low.
    Hi-Lo shelf: Shelf on the high side, shelf on the low side, and a bell in the middle.

    Press the DATA wheel until the "Type" is selected them turn the wheel to scroll through the 3 choices.


    DRA
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    DennisDennis Posts: 801
    DRA

    EAW spec'd bell for 30Hz and I think the OP wanted to confirm it was bell and not shelf
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    MaxxarcadeMaxxarcade Posts: 12
    Gadget wrote:
    Shelf settings??? Assuming you have "ultimate" power for the subs (at least 2X the program power for the tops...) set the Xover @ 80hz BW24, If you have LESS power, raise the Crossover point correspondingly...

    The HPF for the subs is 20 hz (LOL) BW 24...you better have MASSIVE power available.. and there ain't NO way those subs will do 20hz...

    Personally I don't like setting the crossover point on top of the kick drum 1st harmonic...I'd raise it up, to 90-118hz BW18 and be done with it...We also find that the LR24 transition point between top and subs to be very symmetric and pleasing sonically.. the LR24 slope has a 360 degree phase differential that just sounds more musical...

    I am currently using 4 bridged Crown K2's on the subs, a Crown K1 on the mids, and a QSC RMX850 on the highs. I'll experiment with the PEQ this weekend and see how it goes. If I need more power on the mids I can swap in a Yamaha P5000S that I have laying around.

    The subs use RCF L18P200-N drivers. I have them rolled off at 25Hz and 100Hz right now. They will play as low as 27Hz or so before they start to really drop off.

    My tops are sealed 15" 2 way cabs with Eminence Delta Pro 15A for the mids and Selenium D220Ti on fairly large horns for the highs. I plan on building another pair eventually so I can double them up.
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    MaxxarcadeMaxxarcade Posts: 12
    Dennis wrote:
    DRA

    EAW spec'd bell for 30Hz and I think the OP wanted to confirm it was bell and not shelf

    Correct, I was wondering if EAW just wanted a single bell at 30Hz. It confused me because they listed the "type" as parametric, without saying shelf or bell specifically.
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    DraDra Posts: 3,777
    The fact that they spec a "Q" indicated a bell. Had it been a Shelf it would have been "S" (for slope). :)
    At least that make me look smart after the fact. :mrgreen:

    DRA
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    DennisDennis Posts: 801
    Maxxarcade wrote:
    Standing 6 feet away, there isn't much bass, but in the next room, things are bouncing around like crazy..

    Are you sure all of your subs are in polarity with each other? Plug in a mic and gently thump it into your palm....are all of the subs moving in the same direction? Lets assume they are and they are in normal polarity. What happens if you reverse the polarity of all 6 subs...what effect does it have on the bass response in your room and in the next room?
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    GadgetGadget Posts: 4,915
    The fact that they spec a "Q" indicated a bell. Had it been a Shelf it would have been "S" (for slope). :)
    At least that make me look smart after the fact. :mrgreen:
    And BINGO was his name 'O'... :mrgreen:
    Are you sure all of your subs are in polarity with each other? Plug in a mic and gently thump it into your palm....are all of the subs going the same direction? Lets assume they are and they are in normal polarity. What happens if you reverse the polarity of all 6 subs...what effect does it have on the bass response in your room and in the next room?

    A 9Volt batter can also go a long way toward determining polarity problems... with all but some JBL drivers .. plus to + and Minus to - should elicit an outward cone motion...This could also be room modes, or boundary cancellation depending on if were talking kick drum or overall low end response...
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    MaxxarcadeMaxxarcade Posts: 12
    I've checked the subs with a 9 volt battery at the amp end of each speaker lead, and all of them are in phase. Also tried muting and unmuting the mids, and it does get louder at crossover frequencies when unmuting the mids.

    The room is an acoustic nightmare. It's basically a 15x20 room that's L shaped, and has a 6.5 foot ceiling and a concrete floor. If I'm standing near the back wall or on either side of the subs, I have great bass. But it seems to cancel at certain frequencies right at my sitting position in the middle of the room. The speakers are on the longest wall, facing into the 15 foot wide half of the room. I really need to rearrange everything so that the speakers can be on the far end of the room.

    I also got the PEQ set up and working fine, and I just need to tweak everything up again. I have a Dayton Omnimic V2 that will help out with some of the setup. The auto EQ on the DRPA+ tends to kill the bass and bring the mids up too high for my taste. Maybe I'm just a bass head LOL.



    IMG_5199_zpsb03a93ab.jpg
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    DennisDennis Posts: 801
    Gadget wrote:
    A 9Volt batter can also go a long way toward determining polarity problems...

    A nine volt battery is great for testing a speaker box.....at work, we have a bunch of 9V testers built up with switches that can test a 4 way box. The method I suggested will test everything from the mic to the speakers in one motion. Of course it won't tell you where the problem is but just knowing for sure there is a problem somewhere in the chain is half the battle.
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    DennisDennis Posts: 801
    Maxxarcade wrote:
    I've checked the subs with a 9 volt battery at the amp end of each speaker lead, and all of them are in phase.

    you have tested only your speakers and speaker cables but not the rest of the system
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    GadgetGadget Posts: 4,915
    As Dennis said...

    Also, try moving the subs to the CENTER of the room...and see what happens...Next move them to the corner... in the position you have them that could WELL be the problem...

    http://webphysics.davidson.edu/Applets/ ... fault.html

    Move the red dots around and see what happens, without actually modeling the room in it's actuality you cannot even begin to figure out what is exactly happening..

    Try the placement changes even if only using 1 sub... and report back...
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    MaxxarcadeMaxxarcade Posts: 12
    I'll do some testing this weekend. So far I've tried connecting each speaker one at a time, and verified that the SPL does go up with each addition. I think that having the speakers facing into the "pocket" of the L shaped room is causing a bunch of boundary cancellations.
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    GadgetGadget Posts: 4,915
    That is my assumption as well..and why I suggested the alternate positions...
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    MaxxarcadeMaxxarcade Posts: 12
    Gadget wrote:
    That is my assumption as well..and why I suggested the alternate positions...

    Yep, moving them is definitely in the plans. I just need to get a couple people to help, and also need to make space. The room is currently used for storage at the moment and only has a couple narrow areas to walk.


    I had some fun with the system last night though. Turned it up for about a minute, and the bass caused a light bulb in the ceiling above the subs to unscrew itself and shatter on the floor. I would love to move the room around and get that kind of output where I normally sit :D
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    DennisDennis Posts: 801
    Maxxarcade wrote:
    I think that having the speakers facing into the "pocket" of the L shaped room is causing a bunch of boundary cancellations.

    Since the subs are pretty much omnidirectional, where they are facing is a tiny issue compared to where they are located.
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    GadgetGadget Posts: 4,915
    1+
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    MaxxarcadeMaxxarcade Posts: 12
    Dennis wrote:
    Maxxarcade wrote:
    I think that having the speakers facing into the "pocket" of the L shaped room is causing a bunch of boundary cancellations.

    Since the subs are pretty much omnidirectional, where they are facing is a tiny issue compared to where they are located.

    True, I almost forgot about that. I guess I'm still used to dealing with regular 2 or 3 way home speakers, and how they need to be oriented just right for the best sound stage.
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