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Mackie & QSC PLX AMP

Proud dadProud dad Posts: 22
So i down loaded the update on my 260 and The QSC PLX list goes up to 3102 7 then to 3602. Why does it skip my 3402 amp :x
The mackie list does not have my S225 2-way towers, I was surpprised
Do they add to the list often :?:


4ea runnig @ 4 ohms AMP QSC PLX 3402 Digital amp
Mackie's new S218s Precision Passive
500 watts long-term power handling; 2000 watts peak
Single 18\" (457mm) LF driver with incredibly resilient high-temperature voice coil
Frequency Range (–10 dB):
38Hz – 360Hz
Max SPL Long-term @ 1m: 122dB
Crossover Frequency: 180Hz, 12dB/octave
Input Impedance: (nominal) 8 ohms, (minimum) 3.9 ohms @ 110 Hz

2 ea must of the time / some events im running 4 ea. At 2 ohms on the AMP QSC PLX 3402 Digital amp
Mackie's new S225 2-way / Dual 15\" / high frequency horn
700 watts long-term power handling; 2800 watts peak
Input Impedance: 4 ohms

DBX 234 Stereo 2/3 Way, Mono 4-Way Crossover (running in Stereo 3 Way)
Would like to keep stereo, Monitors are not a issue I run the monitor mix on an EQ 31 Band. I assume I will be eliminating the crossover?

DBX 2231 Dual 31-Band Graphic Equalizer. I would like to keep that after the Drive rack (flat) just for quick adjustments and store new venues after the show. copy the settings (if changed) into the 260 and list the venue. Is this a bad idea?
DBX 1074 Quad Gate
2ea. DBX 1066 Dual Compressor Limiter Gate
M-ONE effects processor
Mackie 1604 mixer

I purchased the 260 cause of all the reviews I read. My PA is sounding real good now and I was told the 260 is really going to do a lot for my PA. I was going to go with the DBX PA but I seen a few review were a power loss could result in spike on my cabinets that could be fetal to them. I spoke to tech support and they informed me that is not a problem with 260.
So after all the excitement of receiving my 260 im loss in hooking it up. I thought I new what I was doing but this drive rack stuff is new to me. I want to put it in the FOH rack. Looks like i need a custom snake made. Any tips. I put it in the AMP rack for now and replaced my cross over. Really want it in FOH. Can i just run a 100 ft cable to my lap top? that would be the simplelist method. Dont know if they make a cable that long. Im runing in 2x3. I got The RTA DBX Mic with it. I wont need the alignment /delay yet is my guess.

I'm not Bi-amp or Tri amp yet. In time with extra money. LOL. It never ends but I love it.

I am my sons sound engineer, 6 years and learning all the time. Vintagetheband.com They keep me very busy.

Please help if you can. I will take a hard look at the manual again this weekend. Every thing is Bi or Tri amped and im not at that point YET. The QSC amp can run all day at 2 ohms and surprising it sounds pretty clean. I will get more amps though so I don’t have to run them so hard on the bigger shows.$$$$


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    kpippenkpippen Posts: 551
    Hello Proud dad,

    I would love to jump in...but I'm extremely busy at the moment... If Dra or Gadget chimes in...listen to everything they tell you!...:D

    D and G,...I might be able to post up some visuals this evening after I read your recommendations...8)


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    DraDra Posts: 3,777
    Welcome Dad,

    Good choice (260 over DRPA).
    Have you read the \"Welcome\" post in the \"FAQ\" section? There is a ton of beginner info there.

    Quick answer though for for your 260 to computer question. Assuming that you run stereo tops and mono subs (2x3), that requires 3 snake returns if the 260 is in the mix rack. (stereo tops and subs (2x4) requires 4 snake returns) If the 260 is in the amp rack, then 2 returns are required for the 260 inputs and 1 for the control line (total of 3 regardless of outputs for stereo config). Yes, you can run the control line through the snake by making patch cables from the 9-pin null modem cable that came with the unit. Instructions are available here http://www.driverack.com/drug/view_thread.asp?forumid=25&thread_id=40129 (also in the FAQ, Gadget just added a visual guide)

    After you read the welcome, you can return and ask more focused questions. (The welcome was written by Gadget, Kevin, & myself for just this situation.) We will be more than glad to help will future needs.

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    Mackie's new S218s Precision Passive
    500 watts long-term power handling; 2000 watts peak
    Single 18\" (457mm) LF driver with incredibly resilient high-temperature voice coil
    Frequency Range (–10 dB):
    38Hz – 360Hz
    Max SPL Long-term @ 1m: 122dB
    Crossover Frequency: 180Hz, 12dB/octave
    Input Impedance: (nominal) 8 ohms, (minimum) 3.9 ohms @ 110 Hz

    Mackie recomends Cross over at 140 Hz. I did this today and the subs do sound better around 134. Should i cross over the TOPS S225 Mackies towers at or around 134 to?
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    Buy the way this Forum rocks :D Thanks for the help
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    DraDra Posts: 3,777
    IF you \"filter\" the sub at 134hz, then \"filter\" the tops at 134hz (or a tad higher). That seems high though. Personally, I would cross a dual 15 cab in the 90 - 100hz range. A typical male voice can reach into the 125-130hz range, and you don't want vocal fundamentals in the subs. Remember, in the end it is what sounds best, (all things being equal) is best.

    The only real way to know if your x-over point(s) are set right is to set up a single stack outdoors (away from walls houses etc, in open field is great)and do an auto-EQ. Look for dips or humps at the x-over point. If the is a hump separate the filters a little, etc.

    Be sure to post back your settings and your results. Others can use the info to help them.

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    With a single stack how far should I have the RTA mic? What frequence response should I be using (Flat (0), Response A-D, Low Med And High?

    I have not messed with the Sub Harmonics yet and wont till I fully understand it. I don’t want to hurt my Subs. Ruining @ 4 ohms with amp set in parallel (channel 1&2 connected internally) mode but only using one input and 1 amp. Maybe its time to go Bridged and do a gain set again. 3400 is a lot for my subs is it not? 500 watts long-term power handling; 2000 watts peak. I think I will do that tonight and see what the gain structure looks like. I'm sure the amp will be set pretty low with the 260 8)

    QSC PLX 3402
    Stereo Mode (both channels driven)

    8 ohms 20 Hz–20 kHz 0.03% THD 200W 700W
    4 ohms 20 Hz–20 kHz 0.05% THD 1100W
    2 ohms 1 kHz 1% THD 1700W
    Noise (20 Hz–20 kHz) < -107 dB

    Bridge Mono Mode
    16 ohms 20 Hz–20 kHz 0.1% THD 1400W
    8 ohms 20 Hz–20 kHz 0.1% THD 2200W
    4 ohms 1 kHz 1% THD 3400W
    Input Sensitivity @ 8 ohms 1.9 Vrms
    Input Sensitivity @ 4 ohms 1.7 Vrms
    Output Circuitry 2-Step Class H
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    DraDra Posts: 3,777
    You want to be far enough back so that all components have a natural path to the mic. 10' is usually fine. About middle of the top cab is good.

    Since you will use this set-up as a reference point, use the flat response.
    You can use the data from the auto-EQ to transfer the info from the GEQ to the output PEQ's. Keep re-EQing until unyou have almost no adjustments. For example, you may find a +3db hump in the 2-3Khz range that 1 PEQ filter can fix. You have 4 PEQ filters for each output band. If a majority of the bands in the hi output area are cut, then you can consider lowering the gain of that crossover band by the average about shown or raising the lows's gain. Always clear the GEQ before starting each round. Using the output PEQ's now has freed up the GEQ for indoor auto-EQ. And your system has started as flat as it can be. Can this work against you? Sure, but you can tell if it is by comparing the PEQ setting to the indoor auto settings. But by and large you will be better off by starting with a flat system.

    Gadget despises (harsh) the Sub Synth. Try to get along without it. You may find that music sounds better of a flat system, reproduced as intended.

    There are a couple of rules of thumb.
    1- Match amp output to the Program rating of the Mains speaker (the middle number between Continuous and Peek) Most view this as an amp minimum. Equal up to 50% more is a good range
    2- For subs, it is held that 2.5 times is recommended. Remembering that too much can be bad and not enough is always bad.
    3- Continuous output is rarely reached, where extra power is needed is for the peeks.

    There is lots of good discussion on this subject her and in the Former Forum above. Read up on it.

    Also remember that you are dividing the amps power between the 2 subs AND the 3400w is referenced @ 1Khz. So each sub is actually only getting 1500 - 1700W. WAHLAH. You should be in ggod shape. BE SURE TO SET THE HI-PASS FILTER FOR YOUR SUBS!

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    I played with it for 5 hrs yesterday. :shock: Load out and load in of the gear included.3:30-8:30pm, Nice open field.
    So I think im understanding the PEQ a little more. I believe after you auto EQ and go into the PEQ you should match the graph of the EQ close and smooth as possible. I used the Bell. Not sure I understand the low/high Shelf selection on the PEQ. Do you have a visual example of a EQ and how the PEQ was set for the EQ? A visual can go along way.
    Also I was thinking of going to 2x4 instead of 2x3 and put the subs in stereo. What’s the advantage of this? Subs are not directional. My guess its easier on the AMP. After 5 hrs yesterday and pulling my hair out because the sub AMP was clipping to easy, I was getting ready to go to bed, (10:pm) and it hit me. So I had to check or I would never get to sleep. I unload the AMP rack and FOH rack from the trailer and brought it in the house. Yes I had the speaker wires on the bridge amp + & - reversed. :oops:
    What a shame. So I then decided to go to 2x4 and put the subs in stereo. Then proceeded to do a gain set with the pink noise on my i-pod. By Now its after midnight and I have to go to work in 5 hrs. :( Man I got the 260 fever bad, I have become a sound junky. 8) I don’t know how the subs are going to sound cause I would have woken up the neighbor hood, All though there are a few neighbors I would love to do it to :twisted:
    Rock on
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    DraDra Posts: 3,777
    Subs (stereo or mono) - Some people like to put all their subs in one spot for the summing effect (increased low end). Mono allows you to chain amps together with fewer cables.

    Sub amp clipping - Mono and bridged are not the same thing. Are you bridging the (1) amp and putting all (4) subs on it? If you are, that is probably the reason that you are clipping. You have a 2 ohm load on the amp. The minimum bridge load is 4 ohms. Reversing the speaker wires would not have caused the amp to clip, just make the cone move in reverse.

    PM me your email and I send you an example of the GEQ to PEQ transfer.

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    Dra wrote:

    Sub amp clipping - Mono and bridged are not the same thing. Are you bridging the (1) amp and putting all (4) subs on it? If you are, that is probably the reason that you are clipping. You have a 2 ohm load on the amp. The minimum bridge load is 4 ohms. DRA

    Man don’t i just feel dumb now. :oops:
    I knew that. Some how i was thinking i was at 4ohm. I have just been trying to get this PA dialed in enough to run it and tweak it at shows with a good base line starting point. I have 4 shows this weekend. i take my lap top to work and mess with the Program on breaks. it sure helps a lot. It al seemed so over whelming 2 weeks ago and now its starting to click and come together for me
    . :D
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    GadgetGadget Posts: 4,915
    If I may interject here...

    you REALLY need to make sure that all the drivers are going in the same direction...AND that all the amps and wiring are correct to the speakers so that a positive signal at the speaker inputs equates to all the drivers moving in the same direction. A simple way for you to achieve this is with a 9 volt battery and a cable that plugs into the speakers with one end that you can touch to the battery... with the cable plugged in touch the + on the battery to the + speaker wire and the minus to the - and observe the cone ( this works for non compression drivers) it should move outward (unless it's certain JBL drivers that were wound backwards on purpose... (really confuses the issue...but...) short touches here won't harm the drivers...

    If you place two speakers together and the sound seems to disappear \"then one is reversed polarity... when separated it's harder to tell but when together... gone!

    As for bell and hi and lo shelves...these are PEQ (parametric eq's) that we use to take care of a broad range of speaker inconsistencies, and problems. A good example of a hi shelf is for a CD horn Equalization.. if you want to learn more about why thats necessary go here:
    http://www.peavey.com/support/technotes ... orn_eq.cfm
    Fire up your GUI and select the U1 perset and double click on the post crossover left and right high PEQ (which is linked by the way). Click the \"high shelf\" button and note that the yellow band becomes active... set a 3.08khz center frequency with a 6 db / octave slope and a 6 db level. this would be a typical CD horn EQ.. the lo shelf works the same way just at the other end of the spectrum.

    A bell curve sets a center frequency and a (falloff) slope which can be set very narrow to for instance take care of a higher frequency ring in the mains or resonance on a horn, or anything up to a full 2-3 octave (or more) treatment... say for added bass across the boards...you can set the 4 filters with 1 low and one high shelf and two bells, or 3 bells and a low shelf .. or 4 bells.. or whatever but not 3 shelves.. or two high shelves...

    As for the power question and the lack of a preset for the 3402...the gain structure will set the amp level anyways.. most speaker presets that are for a \"sub\" \"tops\" rig have NO PEQ settings and are generally just starting points.. you don't get PEQ and Delay setups till you get into bi-amp amd tri-amp setups and the like. Unlike Dra you will see my mantra is \"Too much power is never enough!\" this I equate to a Ferrari.. sure it has 385 horsepower and goes 195 MPH.. but does that mean you HAVE to use all the power all the time? No...

    Remember that a outdoor eq sets up the system for flat response that you can store in a preset for recall when:
    1. you have a very reflective room where any excess energy is degrading to the signal
    2. for comparison to the AUTO EQ plot to see what a room is doing to your sound... interpreting that data could prove challenging but... read through those Peavey tech notes ... especially the \"boundary cancellation\" article...and if you haven't done so the FAQ welcome and \"former forum\" tutorials..
    have fun
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    Thanks Gadget

    I only put the banana plugs in turned around. I have a patch panel i had made by Whirl wind for all my(speakon) inputs an out puts and main cables, monitors, made for each side so it is 1 cable per side and splits to high and low at the speaker. Keeps it edit proof until i messed with changing the amp to bridge mono. :roll: Every thing was set before that.

    I’m using The PEQ per DRA suggestion to free up the EQ for inside. The Mackie S215s towers are very good sounding as long as i do something with the Horns. They will rip your head off. I did do a auto EQ with the mic at the center of the horn 4 feet away and it seem to do a lot for taming the horn down. On another note I didn’t pay attention to were i was saving last night and saved over 5 hrs of work :evil:
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    GadgetGadget Posts: 4,915
    shouldn't be THAT hard to find if you actually did save what you did.. check the presets in the first 10 presets for the PEQ settings you used.. if their not there you may not have saved your work...look at it like this.. a learning experience. To store a preset requires three presses of the store button...one to determine where you want the preset... one to name the preset and one to verify that you REALLY want to do it...

    remember that the cheaper RTA mics are not very linear in the lo register, so from 150 hz down you should EQ by ear anyway. the BEH 8000 and RTA M are cheap mics the BEH unit's main downfall is that it is not consistent from mic to mic...I can't say about the RTA M but a better solution is the Audix TR40.

    good luck..

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