P.A Clipping

Hello all, I'm new to this so hopefully i can get some help and guidance.

Basically i have a powered behringer PMP4000 going to EV ZLX 12P active speakers. I'm taking the connections from the non powered side of the desk to the speakers, nothing from the speakon connections.

4 peice band. Bass, both guitars and vocals going into the desk. Our singer has a vocal processor also. I connected all in and turned all down, with the gain i started to put up to i seen it was just fine or in the yellow. Did this with all then then with faders star put volume to FOH. However when we get going its up to red all night. Do i need to change the desk? Any help would be appriciated.
 
So the musicians sandbag mic/line checks and then play/sing louder once you start playing for real. Welcome to live sound... this happenns all the time.

So with that said, if the desk is going into the red that is bad and yes you have to turn everything down, go through all the inputs one at a time and readjust input gains and everything else, and when you do that if you find that your FOH speakers aren't loud enough then don't be surprised... if your band plays loud you will find the limits of those speakers pretty easily.
 
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^ +1.

I've seen drummers hit 20dB harder, going from soundcheck to the show. Some singers aren't far behind that figure. Reduce the preamp gains a bit, and all will be well. The faders will probably need pushing up a bit to match.

If you find the EV speakers are hitting their limits (not difficult with those), a subwoofer or two would help to alleviate some of the stress. Bonus: you can then mic the kick drum (essential IMO).

Chris
 
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Agree and add: how many 12" speakers are you using total???
2? .... 4?

And you apparently sending the Bass Guitar through them?

No way!!!!

Unless playing in a small Club, small Church or School setting.

"Watts" are not enough, you need to move air.
 
Guys thank you so much for the quick responses,
We are using 2 ev zlx 12p speakers we are looking at getting a subwoofer. I was reading about bridging mode to get 1600 out the desk instead of 2 x 800 but not fully understanding how far works. Ye we are sending the bass through but that will stop now, we did 2 his with this gear and it was annoying me, the sound is fine out front but know its not correct.
 
If the sound out front is good, you're fine. Loud bass guitar will overload those speakers, but if the volume levels are sensible (ie, they're not constantly into the limiters), there's no problem with them reproducing bass guitar.


The power output of the desk is irrelevant here - you're using the line level outputs, so it doesn't really matter how the mixing desk's built-in amp is configured.

Chris
 
I have those speakers which I use as DJ monitors (small, light weight, fairly clear sound). They just aren't really loud enough for PA on their own IMO. The 1000 watt rating is very misleading. They will do a job but really you will be ragging them to get any decent level. I have rented mine out along with a 1000 watt RMS sub and that works pretty well for a budget system. So yes definitely get a sub. This wont solve your excessive dynamics problem but your PA will sound a lot better overall.
 
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Add two subwoofers (one per side) and two extra 12" (so two per side) , cut bass going into them (so subwoofers do the heavy lifting) and now we are talking.

Again: "1000W" means nothing, 2 x 12" pushing air is puny,even worse if the full band goes through them.

Specs are physically impossible.

1000 W (Class D); 126 dB max SPL; 50 Hz – 20 kHz
* those voice coils can NEVER take 1000W RMS.
Of course,even if the amps are cable of supplying them to a (watercooled) resistor load, clever limiting and processing will NOT let them reach voice coils, but a much attenuated version.

* 126dB SPL at some frequency? (1000 Hz? For a couple milliseconds? .... maybe.

Definitely NOT at:

* "50 Hz – 20 kHz"
Flat down to 50Hz in that tiny cabinet at low power?
Maybe, with heavy processing, say 10dB bass boost .

At concert levels? .... forget it.
Notice besides the main description (which everybody reads) , there is also the less prominent:
smaller-venue sound reinforcement or stage-monitoring

and nowhere it says you can amplify a full band, including Bass Guitar through it.
 
* those voice coils can NEVER take 1000W RMS.
Of course,even if the amps are cable of supplying them to a (watercooled) resistor load, clever limiting and processing will NOT let them reach voice coils, but a much attenuated version.

* 126dB SPL at some frequency? (1000 Hz? For a couple milliseconds? .... maybe.

I think if you drill into the specs that 1000W is typical PA sales speak i.e. peak which somehow is 4 * the RMS or whatever rating. I have never got my head around the 4* part that some manufactures make up.

Yes, on Thoman that are listed as:
  • Power: 1000 W peak, 250 W continuous power
 
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For a band I would be looking at line arrays and 18'' or 21'' subs in front of the stage. Depending on audience 5-10KW would perhaps suffice.
You could try perhaps a compressor / limiter between the desk and the speakers to protect them..
 
Line arrays require hoists, rigging, and someone who is qualified to deploy them safely. Not the right tool here.


Those EV speakers are competent budget speakers. If I was to use them with a full band, I'd like to use them with subwoofers so that the EVs have more headroom. Having actually used them for live reinforcement, they're not bad. It's pretty easy to find the limiters, but they still sound okay with the limiter flashing occasionally. I'd rather mix through those than almost anything from Mackie, or one of those column arrays that some people seem to like.

It might also be worth moving to a digital desk, so that the sources with increasing volume levels can have compressors to reign them in a bit. That's a whole different discussion, though.


Chris
 
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Perhaps a bit unrelated, but I was at a concert earlier this year, and the wole evening was very nice, until the "big name" main event went on, and shoved every single fader to absolute max. All the amps went into clipping, bass, mid and highs all distorted severely.
I went outside and decided to wait for my brother in law that obviously didn't understand what was going on and thought it was supposed to be like that.

How can people think it's okay to clip all the amps constantly? It sounded horrible, and later one artist came over to me and wanted me to have a look at some Crown amps he was having problems with... Blown output stages.

I think "the talk" is in order, not sure how to approach the subject since apparently "moar loud noize ekwalz moar guud!"

@Duncanmaclean1 you're on the right track since you actually have concerns about clipping, it's a safety feature not a hammer.
 
I just don't like pushing equipment to its limits and damaging it and siunding bad. The lights are there for a reason. I was walking along to a local festival earlier this year, said to our drummer these speakers sound like they are going to pop and we were outside the marquee. After the show i spoke to one lad in the band and i complimented on the RCF speakers they had that they are a good make. He said we're not happy with them at the moment and i told him what id heard earlier, the sound man went by and he told him and all he said was wouldnt be surprised.
Thanks for the comment @KaffiMann
 
Line arrays require hoists, rigging, and someone who is qualified to deploy them safely. Not the right tool here.


Those EV speakers are competent budget speakers. If I was to use them with a full band, I'd like to use them with subwoofers so that the EVs have more headroom. Having actually used them for live reinforcement, they're not bad. It's pretty easy to find the limiters, but they still sound okay with the limiter flashing occasionally. I'd rather mix through those than almost anything from Mackie, or one of those column arrays that some people seem to like.

It might also be worth moving to a digital desk, so that the sources with increasing volume levels can have compressors to reign them in a bit. That's a whole different discussion, though.


Chris
Ah chris, you mentioned there a digital mixer, i was thinking of a behringer xr18 or soundcraft. Im a little old fashioned and like an analog mixer. But i also love tech and with a few youtube videos and time spent with it i do think it is the way forward, compact in a flight case with our in ears etc and adding a subwoofer or 2 would be sufficient i think for what we need. I dont know too much about the digital mixers you recommend any?
 
Depends on your channel list and how you're going to use it.

When I was buying, I picked up a QSC TouchMix 16 as soon as they came out (the iPad app had been released earlier, so I was familiar with the controls). IMO, they have the most "analogue" workflow, in the digital desk world. They're not great for actively mixing (more than one fader moving at once), but I got by with a couple of iPads and made it work.

I moved up to the TM30Pro and have enjoyed the extra functionality. The one I particularly like is this: I can set up an iPad and a set of motorised faders at a good mixing position, and control the desk (positioned side-of-stage) via WiFi. At the time, all the digital mixers would allow you to mix from an iPad. Very few would let that iPad talk to some faders in a useful way.
The TM30Pro has some other useful features which I like, such as custom fader banks (you can have 3x banks where you can choose any channel/FX-return/Aux-send in any order to be your 8x faders for that page) and the USB audio.

All of the TouchMix desks have analogue preamps and gain controls. I don't mind that, but some people hate it. At the time, it was a choice between the TM16 and a black box mixer with no controls on the front. Since I don't like relying on a network for all control, I wanted to be able to control the desk directly. The TM16 offered that, so I went with it.


If you're heading towards IEMs, I'd recommend going stereo. Make sure your desk has enough Aux sends to support that.


Chris
 
I think the best of both worlds in a digial mixer these days has to be something like a Behringer X32 compact, you get a full set of physical controls in a relatively compact package and it can also be fully controlled wirelessly. The family also includes matching stage boxes and personal monitoring systems and it can even be configured to control a second X32 chassis. It also doesn't hurt that this family of mixers has become extremely popular, there are endless videos available online demonstrating just about every feature and there is also a 3rd party control app that is customizable and quite popular. All this would be superficial if these were unreliable but the fact is they have proven to be some of the most reliable digital mixers available.
 
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