Line Array Setup and Angle

[Ivan Beaver]

Re: Line Array Setup and Angle

It's just like tight packing any box - you get more interference between boxes and potentially harsher sound. The idea with line array boxes when they're actually flown is to have the zero angled boxes at the top of the array for more "throw" where they're not covering the near-field. And as you get further towards the bottom, the splay angle opens up to reduce SPL as well as interference for smoother coverage in the near-field. Zero splay of ground stacked line array boxes are usually not very pleasant to listen too.

Of the line array setups that I have walked from front to back and vice versa with pink noise, I have found that the most interference/combfiltering is in the near field.

Maybe I haven't listened to enough line arrays this way--------------------------------------

The basic problem is that the horns are simply not large enough to have any sort of pattern control-except in the top octave or two. As the horn pattern narrows-it has to get larger to maintain the same pattern at a particular freq. And with "10°" boxes-that would require a HUGE horn-to even have control down to 1Khz-to the tune of 8' tall-per cabinet. 500Hz would be twice as tall-hence the issues.

 

[Merlijn van Veen]

A straight coupled line array behaves substantially different in comparison to a curved coupled line array. The two shouldn't be mixed together. The laws of physics prevail. This is why AFAICT i.e. Adamson has a 0 degree splay setting on their rigging hardware, which on closer inspection (Adamadon shooter) turns out to be 0,5 degrees. It's a workaround to avoid problems, but I think it's better to educate.

 

[Cliff Fuller]

Re: Line Array Setup and Angle

This is why AFAICT i.e. Adamson has a 0 degree splay setting on their rigging hardware, which on closer inspection (Adamadon shooter) turns out to be 0,5 degrees. It's a workaround to avoid problems, but I think it's better to educate.

I've never noticed that, hang on ... I'm not seeing any indication of 0.5 degrees. I do see 0.1 degrees, on each increment though. I'll try posting an image. Thanks, Merlijn.

 

[Nick Latkowski]

Re: Line Array Setup and Angle

Sorry Evan found an error in your setup. Probably my fault though as I didn't mention standing room in from of the stage. Anyway, I put everything in with that and came up with this. Tell me what you guys think. I don't think I'll get anymore coverage out of the 4 subs though, if you guys think of any ideas for that or anything else, please let me know.

Thanks
-Nick

Attachments in next post.

 

[Nick Latkowski]

Re: Line Array Setup and Angle

View attachment 7491View attachment 7492View attachment 7493

 

[Evan Kirkendall]

Re: Line Array Setup and Angle

You're wasting too much energy on the near field. More splay down low, and less up top. :

Evan

 

[Nick Latkowski]

Re: Line Array Setup and Angle

Well after setting up today, worked a hell of a lot better. I may still take your advice on that though Evan. And just a dumb general question for anyone to answer, is it better to do this right, and piss off my setup/teardown crew because they actually have to set the arrays up instead of rolling them off the truck already on the subs (as it was done before) or go back to the horrible old way have it sound like shit, and make their lives easier? I'm only asking this because my boss is a little pissed because although it makes a huge improvement, my crews complaining their asses off.

 

[Mike Brown]

Re: Line Array Setup and Angle

Well after setting up today, worked a hell of a lot better. I may still take your advice on that though Evan. And just a dumb general question for anyone to answer, is it better to do this right, and piss off my setup/teardown crew because they actually have to set the arrays up instead of rolling them off the truck already on the subs (as it was done before) or go back to the horrible old way have it sound like shit, and make their lives easier? I'm only asking this because my boss is a little pissed because although it makes a huge improvement, my crews complaining their asses off.

Why even bother taking the PA out of the truck?

Seriously fuck your crews.

It's not about them and their laziness. What about the audience? The band/talent? The people who hired you?

Do it right to the best of your abilities or don't take the gig.

 

[Jay Barracato]

Actually I was thinking that someone had just rolled the boxes off the truck, lifted the tops of the cases, and never got any farther in the setup.

 

[Helge A. Bentsen]

Re: Line Array Setup and Angle

Well after setting up today, worked a hell of a lot better. I may still take your advice on that though Evan. And just a dumb general question for anyone to answer, is it better to do this right, and piss off my setup/teardown crew because they actually have to set the arrays up instead of rolling them off the truck already on the subs (as it was done before) or go back to the horrible old way have it sound like shit, and make their lives easier? I'm only asking this because my boss is a little pissed because although it makes a huge improvement, my crews complaining their asses off.

They are paid to tear down, so why should they complain because you did something tho improve the experience for those attending the show?
Probably because they don't know any better.

I got some beef from the crew at one company I work for because I started using different angels than 0 degrees in their groundstack rigs(4886). Everybody else uses 0 degrees because that is the way they travel in their flightcase and old habits. I set up one side on my first gig in 0, found it less than ideal, and redid it to something more usable. Some of the teardown crew they use thought that this was stupid because it meant more work and "We always do it like this", it took some effort and a demo setup to convince them that it wasn't just for looks but a performance issue.

It's funny how a lot of people understands enough about old style trap boxes to set splay angles and aiming points somewhere "properly" but have no idea how to implement it once it's called a line array. The speakers are still guided by the same physical laws dictated by our universe, so you can apply a lot of the same guesstimating when you don't have any aiming software and get a usable result IME

It's real basic stuff like:
"How come there's no HF on the balcony?" Well, because all your speakers are at 0 degrees aimed at the back wall, put some splay in it.
"But it is a line array". So? How did you use to do it?
"Well, we put some splay between the trap boxes so it would sound more even and made sure that one of them was aimed at the balcony? So why don't you do the same thing with these speakers.
"Because it's a line array" Sigh.......

 

[Ivan Beaver]

Re: Line Array Setup and Angle

It's real basic stuff like:
"How come there's no HF on the balcony?" Well, because all your speakers are at 0 degrees aimed at the back wall, put some splay in it.
"But it is a line array". So? How did you use to do it?
"Well, we put some splay between the trap boxes so it would sound more even and made sure that one of them was aimed at the balcony? So why don't you do the same thing with these speakers.
"Because it's a line array" Sigh.......

And it is obvious that they don't know the first thing about line array behavior-but yet want to tell people how to do it?

There is a REASON they are being paid to tear down- and NOT design/operate systems-----------------------------------------------

 

[Merlijn van Veen]

It appears that some crews that run the same repeating productions, are pretty reluctant to change. Especially when things went "well". To often have I heard "that's the way we've always done it", which pretty much prohibits you from trying something new. Worse case scenario, it didn't work out and involved extra work. I guess some people are afraid of change in general. The challenge is how the effectuate the change whilst keeping a pleasant working environment. New insights over time are not uncommon and we're entitled to put them in practice even if it goes wrong.

 

[Helge A. Bentsen]

Re: Line Array Setup and Angle

Changes are good, it moves things forwards.

I have a specific way of testing new equipment, mostly insert/fx stuff and microphones.

I read the manual and bring it to a festival gig. Nothing beats teasting a piece of equipment under fire where you have to make it work.

It's funny how a lot of people call me insane and reckless because of this approach.
That and refusing to use 0 degrees in a speaker array.

I rigged a large-format array from a known manufacturer from the US using 2 degrees in the longthrow section throwing about 55m to the far seats. Some people thought that this was a really strange thing to do because they always start at 0 or 1 degree in their designs. Never mind that the actual coverage requirements from the number of boxes I had and the desired SPL profile dictated 2 degrees at the top 3 boxes, having a flat portion is important because it's a line array or whatever these people belive. It's just speakers. They interact, they add and substract, the main difference is how well behaved they are at this IMHO.

Sorry for making a mess of this thread. I guess I'm tired of hearing all this nonsense about speakers. Back to the studio

 

[Per Søvik]

Re: Line Array Setup and Angle

I guess I'm tired of hearing all this nonsense about speakers.

Shouldn't be frequenting the forums then :lol:

Acoustics is a very complicated field in many respects, because it is a combination of gas dynamics and the "purer" wave theory that governs acoustics in solids and non-compressible liquids. (If we were fish it would be a lot easier). Line arrays as a concept isn't that complicated, and it isn't really that hard to build line-array boxes. However, just because someone has the money to buy a line-array doesn't mean they have the foggiest idea about how it works, and even attending a week-end course by a manufacturer and receiving a certificate doesn't mean one has even a basic understanding of the concepts, the physics and the mechanics. Separating the nonsense from the truth can be very hard sometimes, and sometimes what might appear reasonable might be totally off, and the wildest nonsense might actually have a degree of truth to it. I believe in keeping an open mind and try to reconcile any theory with what I know about physics and mechanics, sometimes with the help of concepts and principles from disciplines that might seem far removed from the topic at hand, one never know when there is an Eureka-moment just waiting to happen.

As for lazy crews, motivation can go a long way, and taking some time to "Hey you guys, what if we tried this today?" when preparing in the shop might be a good idea.

 

[Helge A. Bentsen]

Re: Line Array Setup and Angle

I've had engineers touring with national acts tell me that you can't use more than -6dB of eq on any given PA because it's bad for the sound. The same people insist that you have to use the correct array correction for the number of boxes. Guess what, the array correction is just an eq. IDK, but why using a factory adjusted low shelf of -9dB is supposedly not bad for the sound but entering the data manually into the processor is somehow wrong just doesn't make sense to me.

These are the same people who can't decide if the xo between lows and subs is correct and will spend a lot of time testing xo frequencies and polarity without any dramatic improvements, because measuring a PA is bad. So i aligned the crossover one day with smaart, told them I'd replaced a broken cable and everybody was happy.

Hopefully you're a wiser man Per
Now, back to the studio.

 

[Jeff Babcock]

Re: Line Array Setup and Angle

My boss isn't big into technology, so an array calc was never used.

Sounds like before your boss worries about technology he should first learn the concepts - I suggest this:
Buy Sound Systems: Design and Optimization


Seeing the original photo and the cringe-worthy PA deployment would make me very nervous that there are other oversights elsewhere. If one of the bands I play with showed up for that gig I would immediately expect a really bad day just based on seeing that. I sincerely hope that is not the case, but the first impression can kill.

 

[Bennett Prescott]

Re: Line Array Setup and Angle

These are the same people who can't decide if the xo between lows and subs is correct and will spend a lot of time testing xo frequencies and polarity without any dramatic improvements, because measuring a PA is bad. So i aligned the crossover one day with smaart, told them I'd replaced a broken cable and everybody was happy.

Oh, man, that's rich Helge. I'm glad you solved their problem without creating a new one.

 

[Ivan Beaver]

Re: Line Array Setup and Angle

I've had engineers touring with national acts tell me that you can't use more than -6dB of eq on any given PA because it's bad for the sound. The same people insist that you have to use the correct array correction for the number of boxes. Guess what, the array correction is just an eq. IDK, but why using a factory adjusted low shelf of -9dB is supposedly not bad for the sound but entering the data manually into the processor is somehow wrong just doesn't make sense to me.

These are the same people who can't decide if the xo between lows and subs is correct and will spend a lot of time testing xo frequencies and polarity without any dramatic improvements, because measuring a PA is bad. So i aligned the crossover one day with smaart, told them I'd replaced a broken cable and everybody was happy.

Hopefully you're a wiser man Per
Now, back to the studio.

It is amazing the crap that MANY people in audio will "spew" out as fact. Somebody told them-so therefore it MUST be true-even though with a just a minimal amount of thought it would be quickly debunked.

I think my favorite was years ago in a magazine article about how to get the most bass out of a club system. It was written by the FOH guy for Blue Oyster Cult-WOW I wish I still had that article.

He described how to make a "special box" that you could easily put into a rig to test to get more bass. It was an AC POWER box in which the neutral and hot wires were swapped. He claimed that this would flip the polarity of the SPEAKER and you could try this and see which way you got the most bass. NOT!!!!!!!!!!!

Can you say-NOT A CLUE!!!!!!!!!!!!!!!!! But he actually had pictures to show how to "wire it properly" for his idea----------

Yet he actually got a magazine article PUBLISHED about the method-which did not work at all as described and could be a shock hazard.

But yet he is probably still out there spouting total crap and some people are probably believing him-----------------------------------

And many people just swallow "hook line and sinker" whatever a manufacturer "sells" them-without doing further investigating and actually applying thought to what is being said and actually measuring or testing for themselves to see if the performance is as claimed.

Oh well------------------------------ We push on--------------------------------

 

[Jeff Carter]

Re: Line Array Setup and Angle

I think my favorite was years ago in a magazine article about how to get the most bass out of a club system. It was written by the FOH guy for Blue Oyster Cult-WOW I wish I still had that article.

He described how to make a "special box" that you could easily put into a rig to test to get more bass. It was an AC POWER box in which the neutral and hot wires were swapped. He claimed that this would flip the polarity of the SPEAKER and you could try this and see which way you got the most bass. NOT!!!!!!!!!!!

On the other hand, if he'd written about how to get more cowbell...

 

[Nick Latkowski]

Re: Line Array Setup and Angle

It is amazing the crap that MANY people in audio will "spew" out as fact. Somebody told them-so therefore it MUST be true-even though with a just a minimal amount of thought it would be quickly debunked.

I think my favorite was years ago in a magazine article about how to get the most bass out of a club system. It was written by the FOH guy for Blue Oyster Cult-WOW I wish I still had that article.

He described how to make a "special box" that you could easily put into a rig to test to get more bass. It was an AC POWER box in which the neutral and hot wires were swapped. He claimed that this would flip the polarity of the SPEAKER and you could try this and see which way you got the most bass. NOT!!!!!!!!!!!

Can you say-NOT A CLUE!!!!!!!!!!!!!!!!! But he actually had pictures to show how to "wire it properly" for his idea----------

Yet he actually got a magazine article PUBLISHED about the method-which did not work at all as described and could be a shock hazard.

But yet he is probably still out there spouting total crap and some people are probably believing him-----------------------------------

And many people just swallow "hook line and sinker" whatever a manufacturer "sells" them-without doing further investigating and actually applying thought to what is being said and actually measuring or testing for themselves to see if the performance is as claimed.

Oh well------------------------------ We push on--------------------------------

Well there's no fix for stupidity. Wonder how many people know that everything's polarized for a reason. Occasionally you can flip the polarity of the speaker, or throw it a little bit out of phase and get better coverage, but never from the power source. That's just dangerous for you and your equipment. Especially when someone tries taking it to the next level and grounds the hot on their distro. After hearing that, I think I'm gonna start testing all power anywhere I go. That's a good way to both kill your equipment, and somebody else.