1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  

Live Show PA Questions

Discussion in 'Live Sound [BG]' started by WiredLlama, Mar 27, 2015.


  1. WiredLlama

    WiredLlama

    Feb 12, 2015
    Johnstown, PA
    I've been playing with two guitarists for a few years and we do about 20 shows a year. We have a basic easy setup: mixer, power amp, two PA speakers and a monitor. We are starting a new project this year and adding a drummer and have a few larger shows scheduled already. By default setting up the sound equipment has always fallen to me and I am fine with that because I have enough knowledge about it to be dangerous but will admit I am far from an expert.

    We are getting some additional equipment and I need some advice or confirmation of my plan going forward. Right now we are piecing together equipment to use for now with plans of upgrading as the funds become available.

    Here is what will be going through the system:
    1 mic'd electric guitar amp
    1 mic'd acoustic guitar amp
    1 bass (DI)
    3 vocal mics
    4 drum mics

    Here is our PA equipment list:
    12 channel powered mixer(650w per channel)( I was planning to use this for monitors and PA)
    600 watt 2 channel amp( I was planning on using this to power subwoofers)
    (2) 300 watt 8 ohm PA speakers
    (2) 200 watt monitors
    (2) 300 watt 8 ohm subwoofers
    Crossover (my biggest concern is how to use the crossover with the powered mixer)
    (We also have available to use an 8 channel mackie unpowered mixing board as well)

    I've gone over numerous ideas but every time I think I have it figured out I think of a reason it might not work. I am reaching out to anyone who might be able to help me figure out how to use the crossover with this system to send the lows to the subwoofers only and keep the lows out of the PA speakers. If anyone needs any further info I can provide it. This forum has been very helpful to me throughout the years. Thank you all in advance.
     
  2. lelandcrooks

    lelandcrooks Commercial User

    Jan 6, 2011
    Kansas
    Owner SpeakerHardware.com
    Mixer model please. It is possible depending on the mixer.
     
  3. WiredLlama

    WiredLlama

    Feb 12, 2015
    Johnstown, PA
    GVD Audio KST880 PMX-12D (Its some cheap crappy Chinese thing that I can't find anything online for. I have a picture of the top of it if that would be helpful at all)
     
  4. tbirdsp

    tbirdsp

    Sep 18, 2012
    Omaha, NE
    Yeah need more info - some powered mixers have "power amp in" jacks - might be possible to take a mixer out into the crossover then run the highs to such an input, lows to the sub amp.
    I have added a sub to a Behringer powered mixer setup without bothering to take the lows out of the mains - not optimal but it worked.
     
  5. WiredLlama

    WiredLlama

    Feb 12, 2015
    Johnstown, PA

    Yea I know I can take a mixer out signal to the crossovers and send the lows to subwoofers and keep the lows in the mains but its not ideal. Of course I realize I don't have the ideal equipment either so I guess I can't be picky.
     
  6. s0c9

    s0c9 Supporting Member

    Jan 9, 2014
    Ft.Worth/Dallas
    1964 Audio artist, Fractal Audio Beta Tester
    What do you mean by larger gigs?
    How many peeps?
    What size room?
    Indoor or out?

    I ask because 650w in a PA ain't much.. especially if you split it L/R between 2-300w speakers. And are you even sure that it producing that much output?
    How to you get the power from the amp to each speaker? Daisy chain?

    The only [google] info I could find on the "GVD Audio KST880 PMX-12D" is that it produces 325w PER channel - 650w total.
    That implies even less [325/2w] going to each PA speaker - assuming the other channel goes to stage monitors.
    In either case, I highly recommend (depending on answers to my questions at the top):
    1 - put vocals ONLY, and possibly kick in PA. Snare will crack enough on it's own
    2 - let backline amps provide guitar and bass levels.

    You can't use a crossover in-line with a powered mixer, unless you take a line out, and (as stated above/earlier) run the LF split from the xover to the sub amp. That will still leave a full-range signal out of the powered outputs going to the tops. Some powered mixers have built-in sub out lines which taps the LF signal.. I doubt this model does.

    Plus, you don't [really] have enough horse-power in that mixer - even if it gave you every single watt that it is rated for - to run a full band mix into it. If you are playing outdoors or 300+ people rooms, you need more PA for that!
     
    Last edited: Mar 27, 2015
  7. WiredLlama

    WiredLlama

    Feb 12, 2015
    Johnstown, PA
    Yea, I know we don't any of the right equipment at this point but we also can't afford to go out and drop a couple grand on new stuff. I'm just trying to figure out how to make what we have work the best for right now. It's all just bits and pieces of systems we've all had over the years.

    As far as the powered board goes all I can say is that on the back of the mixer it says 650w per channel and judging by the overall quality of the thing I agree with you in that it probably doesn't even put that much out. The mixer has L/R output for both monitors and mains so nothing will be chained together. I am assuming (because its what the board says) that the 650w per channel is split between monitor and mains (L/R) sending 325w to each speaker. Could be totally wrong. Its hard to say.

    The venues we have lined up aren't huge so I guess I didn't state my original post with enough detail. I am not really looking to boost our sound a ton. More or less I am looking to even out the sound while adding some bottom end for the kick drum and bass with the subwoofers. I am estimating the PA mains will be used 80% for vocals with just a touch of the guitars added in to add a little 'presence' beyond just the amps.

    Like I said before I am just trying to feel this whole thing out right now.

    Here is another scenario I have considered if you would be so kind:

    -Use the powered mixer for vocals and the two guitars(again 75% vocals, 20% guitars, maybe a little bit of the drums)
    -Use our smaller unpowered mackie board, crossover, and power amp for bass and drums

    I know it would be kind of an unconventional way to mix having two separate boards but this would solve the problem of having the lows in the main mix using the powered mixer only...

    Would there be any merit in attempting something like this or is this just off the wall crazy waste of time?
     
  8. s0c9

    s0c9 Supporting Member

    Jan 9, 2014
    Ft.Worth/Dallas
    1964 Audio artist, Fractal Audio Beta Tester
    I understand budget constraints..absolutely. I have done what you have listed above before with basically running TWO systems for one band!.

    NOT optimal for a whole host of reasons, but it will work.. as long as you maintain balance (levels) between the two and understand that you now have TWO potential sources of feedback, potentially working off of, or independently from each other. With what you have available.. yeah it can work.
    I'd try it at a full rehearsal first - to weed out potential issues - before I did ANY gigs with it... know your gear !! :thumbsup:
     
  9. WiredLlama

    WiredLlama

    Feb 12, 2015
    Johnstown, PA

    Yes, we have planned a 'dry run' rehearsal set two weeks before our first show. There is no way I would walk into our first show never having completely paired up all this stuff first. I've got a good friend with a nice barn(used for small wedding receptions and stuff) that he gave us for the day. My plan is to just dump all of our equipment there and try out all the options and find something that works. While I hope we can find something that works I also hope this motivates some of us to put the investment into some more suitable gear.

    Thank you so much for your input. Not to berate my bandmates but I cannot bounce any ideas about this kind of stuff off of them because that is exactly what happens - it bounces right off of them.
     
    s0c9 likes this.
  10. tbirdsp

    tbirdsp

    Sep 18, 2012
    Omaha, NE
    That configuration would be weird for a powered mixer of this type. Like s0c9, the little I found says two channels of 325 watts each (and I would assume that's into 4 ohms). Normally these mixers are set up so you can run them either stereo left/right for mains with no power for monitors, or mono - one channel for monitors and one for mains. Are you SURE it's not like this? Do you have it in front of you right now?
     
  11. lelandcrooks

    lelandcrooks Commercial User

    Jan 6, 2011
    Kansas
    Owner SpeakerHardware.com
    Are the monitor outs on the Chinese board line or amp level? Unlikely they're driven by the amplifier, that would be really odd. Line level will be Xlr connectors. Do all the mixing on the bigger desk, use the monitor sends to the Mackie using it only as the master for total mix.

    Vocals and kick as recommended above for this rig is spot on
     
  12. ggunn

    ggunn

    Aug 30, 2006
    Austin, TX
    Line outputs can either be XLR or 1/4", and in my experience 1/4" is more common.
     
  13. hbarcat

    hbarcat Supporting Member

    Aug 24, 2006
    Rochelle, Illinois
    You actually have all you need to do what you want (iincluding micing drums) as long as you keep the venue small and don't have unrealistic expectations for volume levels.

    Your goal is to figure out how to use the crossover properly. As you said, making this work with your powered mixer is the key and in order to do this you'll need to use your Mackie mixer to submix. What crossover unit do you have and which mixer model?

    Fear not! This may not be ideal, but it can be made to work.

    Edit: From what little I've found online it seems your powered mixer is MONO out only, but split into two channels, 1 powering mains and 2 powering monitors. They each have their own graphic EQ section. Is this correct?
     
    Last edited: Mar 29, 2015
  14. WiredLlama

    WiredLlama

    Feb 12, 2015
    Johnstown, PA
    I don't have the board in front of me now. I only have a picture of the top of it and not the back where the outputs are.
     
  15. WiredLlama

    WiredLlama

    Feb 12, 2015
    Johnstown, PA
    Yes, from what I can remember there are (4) 1/4" outputs on the back. We have practice on Tuesday. I'll grab a picture of the back of the mixer.
     
  16. WiredLlama

    WiredLlama

    Feb 12, 2015
    Johnstown, PA
    You may be correct about the mono out only. I know there are two EQs on the board. Once I get the picture of the back of the board I'll post both the top and back.

    I don't have the crossover yet. Of course as stated above budget is the number one constraint here so I was just looking at getting a cheaper one from musicians friend. Any recommendations or suggestions keeping in mind 1) Budget, 2) the intended use, and 3) only has a planned usage of maybe a half dozen shows at this point.

    Thank you all so much for your time and input!
     
  17. tbirdsp

    tbirdsp

    Sep 18, 2012
    Omaha, NE
    A long shot for inexpensive gear - but what model is the power amp? It *might* have a low pass filter built in so you could skip the crossover.
    I still say the easiest/most practical way to do this is just add the sub and run the PA tops full range. If you need more low end you can turn up the volume on the sub (rather than boost low end on the EQ), which won't increase the lows going to the tops.
     
    Last edited: Mar 30, 2015
  18. ggunn

    ggunn

    Aug 30, 2006
    Austin, TX
    A lot of times there will be a switch/button where you can select either stereo FOH output on two power amps or mono FOH on one and monitors on the other.
     
  19. WiredLlama

    WiredLlama

    Feb 12, 2015
    Johnstown, PA
    It does have a built in crossover however in that mode it only runs the lows out of one channel (QSC GX3). I would rather use both channels if possible to get the full 300 watts at 8 ohms to both subs rather than split 425w at 4 ohms. Unless that doesn't make sense...
     
  20. tbirdsp

    tbirdsp

    Sep 18, 2012
    Omaha, NE
    Gotcha. You know - I would try it that way though. The difference between 212.5 watts X 2 (chain your subs together for 4 ohm load and then run one side at 425 watts) and 300 watts X 2 probably isn't that much. Saves you from buying a crossover and solves the problem of the mains having the low end in them.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.