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Author Topic: DIY PA advice/troubleshooting  (Read 3413 times)

Kevin McDonough

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Re: DIY PA advice/troubleshooting
« Reply #10 on: May 26, 2018, 03:05:07 PM »

hey

Like everyone else, I have to agree that the speakers were probably inadequate for the job.

In terms of providing vocal reproduction for a loud rock band such as you describe, the speakers would probably be a bit small anyway and you'd really struggle to get even vocals up above a loud band sufficiently, but I don't think in that case they'd have broken in the same way.

I think the problem in this case was probably low frequency and clipping.

Every speaker, without exception, needs a filter to take out the lowest frequencies. For subwoofers this can be somewhere around 30-40Hz, for top speakers anything from 60- 100Hz. Playing frequencies below the limit that the speaker can handle can very quickly cause the speaker cone to overexcurse (move in and out much more than it should) to the point where it can cause damage.  Again, simple vocals wouldn't have caused this too much, there isn't a massive amount of low frequency. But electronic is unfortunately famous for its low frequency content, much more than other types of music.

Quote
the performer did not have total control over our PA but was plugged through our mixer which was at 3/4s volume and the power amp was at 1/3 on it's db knob....

Secondly, I think this is a huge problem, but something that is often a little counter-intuitive without some experience or sound knowledge.

When putting together a PA system, it's always recommended that you buy a power amp that is around 1.5 or 2x the power rating of your speakers. Some people initially baulk at this, wondering why you don't buy a power amp that has the same rating as the speakers, but headroom is the key.

If the amp is the same power rating as the speakers, then usually to get the volume you'd like you end up running the amp close to it's limits, which results in distortion and clipping being added into the signal being sent to the speakers.

Alternatively, if you have a power amp 1.5-2x the size of the speakers, and run them at sensible power levels, you know that the amplifier is running comfortably within its limits you are providing CLEAN, undistorted power to the speakers. While, with the bigger amp, some spikes or loud parts of the music may be a little over the power rating of the speakers, as long as it's clean signal (that's high passed properly as in the other point) it'll handle these fine.  Even at a lower volume, a distorted signal will cause a massive heat build up in the voice coil and be much more damaging.

Most professional sound engineers would have amplifiers fully turned up for the most part (unless the had a reason not to) and would have just controlled the volume with the mixer. But by only turning the amplifier up to 1/3 of its volume you may have artificially put yourself in the position where the amp was clipping it's signal as the DJ's/musicians turned things up at their end to try and get the appropriate volume, and so burned out the voice coils.

(DJ's can also be equally guilty of clipping things at their own mixer and control surface, the often run things into the red, and this would have had much the same effect, and been compounded by you having your amp set too low.)


In any case, I echo everyone else's advice in that powered speakers have all of this taken care of. The have appropriate filters and EQ built in and are largely idiot proof. While of course poor handling can physically damage them, at least in terms of the music signal sent to them you need to do something especially silly to blow or damage them.
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David Pedd

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Re: DIY PA advice/troubleshooting
« Reply #11 on: May 26, 2018, 03:06:03 PM »

ok I'm thinking you guys are maybe too high in your standards...

LOL!  Amen!  That's why I love coming here and reading/learning.  These guys/gals know their stuff.
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Paul G. OBrien

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Re: DIY PA advice/troubleshooting
« Reply #12 on: May 26, 2018, 03:25:08 PM »

ok I'm thinking you guys are maybe too high in your standards for what I'm operating. Gonna just got with the JBL EONs maybe a 15" that I found used for a good price instead... but no I can't afford 2 $500 speakers!

Well OK.. good luck with your venture and I mean that sincerely. You are setting off on a path that many of us have traveled and have witnesses numerous times so even though you don't believe it now our standards are not too high. You say you can't afford to buy two $500 speakers but after you repair the borrowed speakers and buy some of your own you will be well on your way to spending that much anyway, and given that the speakers you are buying are roughly equivalent to those you blew to smithereens on the last gig the school of hard knocks says you will spend at least that much before you arrive at a long lasting solution.
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Debbie Dunkley

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Re: DIY PA advice/troubleshooting
« Reply #13 on: May 26, 2018, 03:48:54 PM »

And as Paul said - buy 1 good powered speaker - not 2 sub par ones...much better idea.  That way you get decent quality to start with  and can add another speaker  down the road if you want to. Just make sure to get a current model and not something being phased out.
 You don't HAVE to use 2 speakers for PA.
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Matthias McCready

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Re: DIY PA advice/troubleshooting
« Reply #14 on: May 26, 2018, 04:02:41 PM »

Hi thanks for your input!

to clarify, this is a house show space as in literally in the living room of my house where I live. so not a venue perse. Think of this application as if you wanted to see a band perform in your living room or perhaps getting a PA for a small venue or practice space is also comparable (amps turned up to drums and usually 1-3 vocals mic'd to be above the instruments, occasionally a horn mic'd and occasionally an electronics rig plugged in through the mixer) typically loud rock... does that give you a better idea of the room/application? sorry for any confusion in my op

This sounds like more of jam and hang out space too me. I think for a living room, to get around drum level (sure the drums will overpower some) that some cheaper PA speakers would be ok. Will they sound great? No. Will they get insanely loud? No. Obviously, though the main goals appear to be price and that it works, not maximum fidelity or volume.

If you want some low-end, many speakers with a 15" should provide a more than adequate amount for a living room.

I often see Mackie TH-15A's for pennies on the dollar. Yes, they sound horrible, but they do have quite a bit of oomph for a cheap speaker (should work for a DJ in a living room).

JBL Eons would work, although I hate them equally as much....

What area do you live in? Perhaps there is something on Craigslist or reverb nearby for a good price. Look for powered stuff by EV, JBL, Mackie, and Yamaha. Avoid Behringer, Samson, and other small brands. Finding something by the four mentioned brands for ridiculously cheap should not be impossible. As long as your expectations are appropriate to the limited budget they will provide adequate results. If you use the speakers as intended they should last.

EDIT: By all means buy one good speaker over two crap ones, if it comes down to that.
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Luke Geis

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Re: DIY PA advice/troubleshooting
« Reply #15 on: May 26, 2018, 06:31:15 PM »

I hardly feel calling you naive is belittling or insulting, but I feel better knowing I gave you solid information. Lets call it hard love. If I was gentle and said you can do what you want on a zero budget, you would go and get the cheapest speaker you could find. Then when it didn't work I would be teh asshole who had you go out and spend money on absolute junk. Now that would be a dick move.

I think the JBL EON 610 is a little too small for what you are looking to do. You will need the 12" or bigger. If cost is really that big of a deal, then I know you could afford the EV ZLX-112p which can be found on the same site for $350. That is $50 cheaper than the JBL and is a 12" model. I think the EV ZLX will be just a superior  option.

We are trying to save you from yourself. Experience and let's face it, a little bit of math, tells us what is capable or not. There are things that money will buy. In this case, quality and capability are what that money gets. Not all cheap speakers are alike. You could save a few bucks more and go get a Harbinger unit, it may get loud enough, but it has no features, sounds like absolute hell and may not last 2 shows doing what you are looking to do. We suggest a safer path by getting higher end names because they typically sound better, have at least some features and the warranty is usually better too.

If we go soft on you, you will defy the logic and you will race to the bottom. If we say you must spend at least $500 to get the results you want, it is probably true. If we say you can get away with spending less, but it's going to be close, then we haven't done you any service at all. Becuase telling you that will make you shot right for it. Case in point, I prescribed all 12" models and provided the model numbers and costs for you. You decided to go with one that wasn't even on my list ( while still in the same model range at least )!!!! This Is why we are so dickish about what to get.We say get this and you / others go and get that instead.

We are no snobs about gear because it suits us. We are informed, educated and experienced enough to know what will get you the results you wish to acquire. No more, no less. So you can take a little bit of criticism and run with it, or you can say that we are snoby, rude dickheads that just want to pick on newbs. Either way you are getting gold here. It's a matter of perspective. We aren't dicks because it behooves us, it's because it behooves you.

While the JBL EON 600 series isn't my first choice, it is far from the last. It doesn't sound that bad considering its price. It is a real entry level powered speaker. It isn't going to make you scream hell yeah, but it didn't break the bank either. I honestly think the EV ZLX-112P is probably the best cheap option available.
« Last Edit: May 26, 2018, 11:05:14 PM by Luke Geis »
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Callan Browne

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Re: DIY PA advice/troubleshooting
« Reply #16 on: May 26, 2018, 07:39:30 PM »

Sure, rush in and buy the eon's because they match your budget - I did exactly the same thing when I first got into owning a pa.

So next year when you want to "upgrade", budget that your almost new eon speakers are worth less than half what you'll pay this weekend so you'll be basically starting over.

PS : just buy one dxr15 and you'll be fine.
I've done many gigs using just a single speaker. It really does work great for small and/or narrow rooms.

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Matthias McCready

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Re: DIY PA advice/troubleshooting
« Reply #17 on: May 26, 2018, 10:21:26 PM »

Sure, rush in and buy the eon's because they match your budget - I did exactly the same thing when I first got into owning a pa.

So next year when you want to "upgrade", budget that your almost new eon speakers are worth less than half what you'll pay this weekend so you'll be basically starting over.

PS : just buy one dxr15 and you'll be fine.
I've done many gigs using just a single speaker. It really does work great for small and/or narrow rooms.

Sent from my Pixel using Tapatalk

The question is does he really want to "own" a PA. Personally, I would set the bar of need and quality before considering budget, such as you point out, that does not seem to the be the natural disposition of the OP. If he plans on growing the system and becoming more "professional", the intended direction of these forums, then by all means to settle would be a costly mistake. I think most of us here are well endeared to the mantra of "buy once cry once."

However, if is he is simply looking for essentially a large stereo system for a hangout space which will be used only for living room jams, I think there are many cheaper products which would adequately do the job, albeit with no standard of professionalism (I stress not with fidelity, clarity, or volume). At the end of the day, a name brand and inexpensive powered speaker will work in this role for years to come if used within its limits, and even such a cheap speaker would be far better than many practice room systems (at least the ones I ran into in my early formative years).

From my perspective, and perhaps I am wrong, the desires of the OP seem more akin to "lets amplify some vocals along with the guitar and drums" or "what would be ok for a DJ to use for a small living room concert/get together." I don't think the OP is asking for professional advice, and is perhaps on the wrong forum.

For better or worse he is enamored with the idea of PA speaker, maybe a cheap one would suit those needs fine, or maybe he will get the bug and it would be a complete waste of money. His inclination should reasonably define the approach.
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Lee Douglas

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Re: DIY PA advice/troubleshooting
« Reply #18 on: May 27, 2018, 12:22:31 AM »

At this point in the thread, the suggestions being made are not about fidelity, clarity or volume.  It's about encouraging the OP to purchase something that stands a chance of making it through, or even to a second gig. 

To the OP: Are these shows for profit or even a break even proposition?  If so, you might try using a sound company to bring the appropriate rig for the gig and a tech to run it for a show, so you can see where you want to be with this whole enterprise. You may find that your expectations are higher when you know what's possible.
« Last Edit: May 27, 2018, 05:31:16 AM by Lee Douglas »
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Callan Browne

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Re: DIY PA advice/troubleshooting
« Reply #19 on: May 27, 2018, 05:42:06 AM »

The question is does he really want to "own" a PA. Personally, I would set the bar of need and quality before considering budget, such as you point out, that does not seem to the be the natural disposition of the OP. If he plans on growing the system and becoming more "professional", the intended direction of these forums, then by all means to settle would be a costly mistake. I think most of us here are well endeared to the mantra of "buy once cry once."

However, if is he is simply looking for essentially a large stereo system for a hangout space which will be used only for living room jams, I think there are many cheaper products which would adequately do the job, albeit with no standard of professionalism (I stress not with fidelity, clarity, or volume). At the end of the day, a name brand and inexpensive powered speaker will work in this role for years to come if used within its limits, and even such a cheap speaker would be far better than many practice room systems (at least the ones I ran into in my early formative years).

From my perspective, and perhaps I am wrong, the desires of the OP seem more akin to "lets amplify some vocals along with the guitar and drums" or "what would be ok for a DJ to use for a small living room concert/get together." I don't think the OP is asking for professional advice, and is perhaps on the wrong forum.

For better or worse he is enamored with the idea of PA speaker, maybe a cheap one would suit those needs fine, or maybe he will get the bug and it would be a complete waste of money. His inclination should reasonably define the approach.
Yep, just trying to lead the horse to water.

Sure the Yamaha is $0.01 dearer than a pair of eons at the candy shop, but it has a $100 rebate.
If nothing else I'm trying to save the op money (short and long term) and put a smile on their face.

The op has already blown speakers, made a regret purchase and has come here for help. So far the help offered hasn't been what the op wanted to hear. We can only hope they at least sleep on the decision and take on the advice offered.

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ProSoundWeb Community

Re: DIY PA advice/troubleshooting
« Reply #19 on: May 27, 2018, 05:42:06 AM »


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