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No Low End

WitchsMarkWitchsMark Posts: 116
edited August 2008 in PA General Discussion
We played a gig back in May and have been in the studio recording since. Tonight I finally got to where I started putting our Practice Studio back together and when I hooked up the Console with the DRPA I was only getting High end through the horns. After much trouble shooting, I bypassed everything and went from Mic - Mixer - PowerAmp - to SP2(1/4\" Parallel 8OHM jack)... still nothing but the horn is working... in both Peavey SP2's. I plugged that setup into a 15\" Monitor sitting nearby and all was well. What could be wrong with my SP2's to have only the horns working??

Comments

  • GadgetGadget Posts: 4,915
    sounds like you did something to the amp rack where the connections to the speakon connectors are, or perhaps you loaded the wrong program into the DRPA? go over the set I gave you and see whats changed...

    Have you run a cable from the lo outs of the DRPA to the amps for the subs?

    Have you verified all cables are hooked up as I specified?

    what are the input and output lights in the DRPA doing?

    try a signal to the lo amps and see what happens

    G
  • WitchsMarkWitchsMark Posts: 116
    Hello Gadget. I actually took the DRPA out of the lineup completely for troubleshooting purposes and went straight out of one of my power amps and into the Full Range input in the SP2. I still get just highs, no,lows at all. I unplugged the SP2 and ran into another 15\" Peavey Monitor I had sitting nearby just to make sure I was gonna get low end out of it and I did, so there is definitely something wrong with the SP2, not the DRPA. If I blew the 15\" Blackwidows in the SP2's wouldn't they still make a noise but all crapped up and distorted?? Could I have burned out the X-over in the SP2's??
  • GadgetGadget Posts: 4,915
    Well, I went to the site and the SP2's have:
    Bi-amp input via 4-pin switching Neutrik Speakon
    The key word here is switching, that would mean that when the NL4 was in the speaker the xover would be interrupted...did you disconnect it?

    It's easy enough to verify if you fried the woofers, and no they don't always make scratchy noises...they may be open circuited, or the cone may be frozen...pull a woofer out and with a 9 volt batters (a couple paper clips or wire may be needed) touch the battery to the speaker and it should move and make a clicking sound.

    try that first, and verify that the woofers are good... you can do the same thing with an NL4 connector connected to the speaker at the jack...put the battery across the 1+, 1- terminals and the same should happen...

    G
  • WitchsMarkWitchsMark Posts: 116
    Yes I disconnected the NL4 before plugging the other in. I will check the Subwoofer by doing what you said and see if it moves when I get home from work. Thanks.
  • GadgetGadget Posts: 4,915
    We ARE talking about the 15\" in the SP4 correct? Because it is technically NOT a sub, only a woofer...
    G
  • WitchsMarkWitchsMark Posts: 116
    yes... sorry bout that.
  • WitchsMarkWitchsMark Posts: 116
    I went ahead and attached a 9-Volt battery to the +1, -1 and right away on both speakers I got a small click initially, but then after that initial small click no movement or nothing from the speaker tapping the wires off and on..... silence nothing. So I am assuming that the speakers are blown. Regardless, when I bought these I also got the extended 12month warranty so I am in the process of getting them back to Peavey for fixing. I just hope I get them back before our August 17th gig.
  • GadgetGadget Posts: 4,915
    I would be really surprised if they cover blown woofers...didn't you set the gain structure up like we specified? If you had you would have clipped the whole rig at the same time...

    They usually call the cooked voice coils abuse and you'd be charged for baskets at least I bet...

    Gadget
  • WitchsMarkWitchsMark Posts: 116
    Yes all was setup exactly how specified. I don't know what happened. In fact everything was working just fine when we had our last gig. That's what is weird is that everything was fine, and now 2 1/2\" months later I go to plug them in and nothing.... it's a true mystery.
  • dkraueldkrauel Posts: 9
    Is it possible they were handled rough and the speaker cone got displaced. Ive had trouble shipping speaker enclosures that worked when shipped but arrive doa with no sign of damage, come to find out the voice coil got jarred and can get hung up and not able to move...unfortunately resulting in re-coning.
  • WitchsMarkWitchsMark Posts: 116
    Got an answer back as to the problem. There was way to much power sent to the speakers form the AMP and melted the Voice Coil. Ohh well. I originally setup the Gain Structure as demonstrated, but I skipped the Limiter part of it. This time after I get my speakers fixed I will go ahead and setup the Limiters too for extra protection.
  • GadgetGadget Posts: 4,915
    DUDE!

    You flunked gain structure totally! The idea is to get the equipment all talking the same language AND determine where the CLIP point of the system is...theoretically, when the mixer clips, the Driverack AND amps should still be in a NO CLIP situation!...

    Also, lets clear something else up. You most likely sent too little AC voltage to the speakers and FRIED them with DC voltage which is actually TOO LITTLE power. (when the power supply gets exhausted it flatlines at the voltage where the amp power supply gets exhausted.. this is then replacing good clean AC voltage with voice coil barbecuing DC voltage!)

    If your running that EP 2500 in stereo you have only 450 watts of power on a speaker that can take 2400 watts of clean power, In parallel bridged you would get 2400 watts, BUT thats for both speakers and each only gets 1/2 of that or 1200 watts.

    What did you have your HPF set at?

    G
  • WitchsMarkWitchsMark Posts: 116
    The idea is to get the equipment all talking the same language AND determine where the CLIP point of the system is...theoretically, when the mixer clips, the Driverack AND amps should still be in a NO CLIP situation!...
    This is exactly how my system was setup. I was fully Gain Structured as per the instructions on this site, except I decided to skip Mr. Dra's \"Super Duper Limiter Procedure\". In fact, the Mixer never did clip, as nor did the AMPS.
    If your running that EP 2500 in stereo you have only 450 watts of power on a speaker that can take 2400 watts of clean power, In parallel bridged you would get 2400 watts, BUT thats for both speakers and each only gets 1/2 of that or 1200 watts.
    I know you deal with alot of people on a daily basis so I don't expect you to remeber, but you actually spent a solid week with me via e-mails and phone calls helping me setup my system. My EP2500 is in Bridged Mode, and you actually gave me the wiring diagram to set it up so I could Bi-Amp my SP2's.
    What did you have your HPF set at?
    You told me to set it at [50Hz to 100Hz BW18 lows ], [105Hz - 1.60KHz mids LR24], [1.60KHz on up for highs LR24].

    I just hope it doesn't happen again. The worst part is that it doesn't make any sense why it happened to begin with. I had played atleast 20 practice sessions with this same exact setup(granted not as much power at practice as a Live gig obviously) and atleast 1 gig prior to the destructive one, and there was no problems, everything was beautiful. If I atleast new what was done wrong I would feel better because I could then avoid it. Something tells me these Behringer AMPS although cheap are just a huge mistake. My sales guy/tech at GC is tending to think that the AMPS may be at fault with surging and what not.
  • GadgetGadget Posts: 4,915
    I have bought 4 of theses and a friend has 6, I have had 2 minor failures and 1 major that was covered under warranty...I beat the living HELL out of mine (the actual brand is NADY and those, the BEH and the QSC RMX are ALL built in the same factory...just with different \"badges\") but I have never cooked a driver.

    Are you SURE that when the gain structure was done, that with the mixer @ clip, the driverack still had PLENTY of headroom (no yellow or red lights above the output, or input meters)? AND that the amps still had NO RED LIGHTS?

    Are you sure you didn't put the LIMITERS on, on the amps? That would reduce the power by almost 1/3 and increase the duty rate of the amp (normally an amp only works in the 10-50 % area with the peaks and valleys of the music)

    I can pretty much guarantee you that that amp was clipping...the power supply was exhausted and the DC current fried the voice coils...The local GC gooks are clueless in most cases...I have POUNDED at just below clipping on those amps even full range, all day and all night and never had a problem,, I got the passive xovers smoking hot once :shock:...

    I remember you and our talks very well...you are missing something.. re-check those amp settings:
    switches 4,5,6,7, pushed right ->
    switches 1,2,3 and 8,9,10 pushed left <- As your looking at the back of the amp...

    Make CERTAIN that when you do the gain structure that you DO NOT clip the input signal on the input channels, and that the LIMITERS and COMPRESSORS are OFF on all equipment!
    That with the OUTPUT meters of the mixer at JUST BARELY clipping (a flickering red light occasionally only...) that there is still 3-6 db of headroom on the input, and outputs of the DRPA(more would be better).
    That the amps , when turned up to clipping are then turned DOWN by 3 - 6 db for headroom.

    Now... when you get this mess all straitened out, with the system up and running and at OUTDOOR concert volume... have the drummer kick the kick drum repeatedly and if he has a double kick that he pound the livin hell out of the bass drum and observe the clip lights on the DRPA and the amps, this is with the limiters OFF... if the lights are hitting on EITHER, the transient peaks will get through the limiters and you will have the SAME thing happen!

    Gadget
  • WitchsMarkWitchsMark Posts: 116
    It is possible the EP2500 started clipping out as I was on stage playing and I am going off what the Sound Guy says, so. When I did my gain structure I started clipping the EP2500(red light bouncing on/off) at the dial set to 30 and maybe even a little above that on the AMP. Then I turned it back to 28, where I maintained a solid Green. Is that relatively turned DOWN by 3 - 6 db for headroom??
  • GadgetGadget Posts: 4,915
    Possibly, but if you set it WITH the limiter on, it's invalid...The MAX system level needs to be determined and THEN the headroom set up and the limiter engaged.. the Limiter should ONLY be a mistake catcher, not a system max level setter...

    G
  • WitchsMarkWitchsMark Posts: 116
    I got ya. I have never had Limiters engaged on the AMPS or the DRPA. My idea was to redo the Gain Structure when I get my new SP2's, and then after that is setup and done, THEN setup the Limiter in the DRPA as per the instructions on this site.
  • WitchsMarkWitchsMark Posts: 116
    Well, I got the new SP2's, lucked out and the warranty I purchased with the speakers replaced them at no cost. I did a new gain structure on Friday, and I don't know how this happened but the first time I did a gain structure I was waaaaaaaaaaayy off. My old GS(Gain Structure) setting had my Mids Amp set at 26 on the dial, Lows at 28, and Highs at 28. This time I was at Mid=20, Low=16, high=20. After this I used DRA's Limiter settings and did that too for extra protection. I think I know where I went wrong. When I did the Gain Structure the first time all was well up until it came to Step#8, I could not get the Master to clip, it stayed a solid Yellow just before the Clip Light, so I figured close enough(I know Gadget, I know). This time I bumped up the Channel with the Pink Noise slighlty and I was able to get the Master to start barely clipping. I don't know if this was the difference or not, but I got a huge difference in the AMP settings, and now when my Master slider is at -10, I get some serious SPL from my system..... alot more headroom.
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