Line Array Setup and Angle

N

Nick Latkowski

Freshman
Jul 17, 2013
60
0
0
27
Pittsburgh
Hey guys. Been doing a venue for the regional company I work for for the past month or so. Still have about 6 shows left this summer. Place is about 150' wide, seating starts at ground level about 15' away from the edge of the stage, has a depth of 45' and rear height of 25'. Stage is 28' Wide, with 8' sound wings. Current configuration of the Arrays, (way my boss "suggested" it) is 2 stacks of 3 TVI w210 (Coverage is 100x10 Degrees) per side (Ground stacked) angled @ 6 degrees per cab on top of 2 TVI 218 per side on sound wings about 4' off the ground.

Problem: Various complaints no one can hear starting around 2/3 of the way up the seating, and to get them to hear well, I hit about 115db closer to the bottom. Way to loud as I'm sure you all know.

Question: Would it do me better to go against my boss's judgement and stack 6 cabs instead of 2 stacks of 3? I would love to fly them, but sadly it is not an option, neither is bringing more equipment.

-Nick

Pic of current setup.
 

Attachments

  • DSCN5510.jpg
    DSCN5510.jpg
    224.4 KB · Views: 3
Re: Line Array Setup and Angle

I don't think TVi has array prediction software. And I'm pretty sure having a 100 degree wide boxes side by side isn't a good thing.
 
Re: Line Array Setup and Angle

Greg Cameron said:
I don't think TVi has array prediction software. And I'm pretty sure having a 100 degree wide boxes side by side isn't a good thing.
Click to expand...
less ur dave rat or bob leonard:roll:

yea go 6 high if manufacture says u can
and u feal its on a safe surface from walking and tipin
 
Last edited:
Re: Line Array Setup and Angle

I'm quite confused why anyone would want to make two stacks side by side like that!? That's asking for even more interference than an array inherently has to begin with.

If allowed by the manufacturer and doable, safe in the situation and all that - surely, I would stack them 6 high. That's how they're designed to work and geometrically it will improve your front-/backrow ratio. Not by a lot, but still... Maybe angle the top boxes less if at all.
 
Re: Line Array Setup and Angle

I guess the fly-attachments for the stage will not handle six flown boxes, but that is definitely what that set-up needs. Assuming you are inventory-limited to six boxes per side, having Wenger make some fly-attachments that gives you 600 lbs flypoints six feet above the roof lip would really do the trick (assuming the structure and hydraulics could handle it). When it comes to coverage and control, elevation rules, and trailer stages in general are sadly lacking in this department.
Short of flying, stacking as high as possible with the top four boxes at zero degrees between them aiming for the top row is likely to be the best solution.
Obviously, a lot of the sound energy will miss the audience completely, but as long as there is nothing behind that will be disturbed by the projected sound, this is probably your best compromise.
 
Horizontally, everywhere where the stacks overlap and are equally loud, the coverage has effectively been reduced to 45 degrees. In other words, at equal levels, 4 times more powerful or twice as loud but less than half the coverage and most likely some serious interference.
 
Re: Line Array Setup and Angle

I also do not understand the two arrays per side unless you are running a dual or A/B system (e.g. one stack for vocals, one for instruments), but as to the main question, I don't think TVI has ever offered any prediction software or the technical information necessary to asses how to apply their products to specific uses. Your best option is probably to contact TVI directly and ask them what they recommend for that specific application, I'm interested to hear how they respond.
 
Re: Line Array Setup and Angle

Stacked in the carts... probably six high is not safe.

You could pretend that each stack is basically a trap cabinet, which is what your boss probably did to come up with that setup. One stack on each side could be angled quite a bit higher to be the "cabinet" that covers those upper seats. Then you can push the highs on that stack a bit hotter since they won't be blasting into the lower seats.
 
Re: Line Array Setup and Angle

Thanks guys. My boss isn't big into technology, so an array calc was never used. I used d&b array calc and just found cabs with similar specs to use with it the other day. It came out best doing what Evan said. I'll see how it turns out this weekend. Only problem with that is they're bi amp and I only have one amp for every two cabs. I'll see what I can do this weekend though. Sorry if I don't reply quick. I'm at Warped tour today.

-Nick
 
Last edited:
Re: Line Array Setup and Angle

Nick Latkowski said:
I used d&b array calc and just found cabs with similar specs to use with it the other day
Click to expand...

Yes, I was going to suggest that, and a Q10 prediction might give you some general idea although those boxes are pretty directional down to 400 hz. predicting with 10A-D is probably as close as you are likely to get without having specific data for the TVIs. Except they are better sounding ;)~;-)~:wink:
 
Re: Line Array Setup and Angle

Are those in lids or small platforms? If lids I would recommend taking them out and putting them on the stage for stability, especially if you plan to angle a stack with more boxes. When I go more than 4 or 5 high with most arrays I'll use sandbags/stage weights/ratchet straps to keep it from even thinking about being able to tip.

And I agree with Even, I think the lip fills are a great idea for that stage and 5 high will give you better coverage, and you could always bring the volume of the bottom two boxes down if you're still crushing the first few rows.
 
Re: Line Array Setup and Angle

I would highly recommend that in the future your boss considers getting a stage with truss to fly the rig. Ground stacking a line array is never ideal, it's not what they're designed for though it's certainly useable with the right setup. A line of 6 boxes a side with the proper splay angles (which will be impossible to know or sure without TVi providing usable EASE data which they probably don't have) will go a long way to give useable, relatively even vertical coverage and get rid of what must be horrendous comb filtering with the side by side 100º boxes. And I'd put the subs on the ground clustered center stage.
 
Last edited:
Re: Line Array Setup and Angle

I retract my statement from earlier. Got home, and got on my computer. Plugged in the d&b V12 in the array calc(120 degree box, about as close as I can find to your box), and I ended up with the following:

Frame to bottom box: -7 (Hopefully your frame allows this) Box -6dB
8 -6dB
6 -4dB
5 -4dB
3 0dB
2 0dB

Looks like about 6dB difference between the front and back. Probably as good as it gets with a ground stack array in this situation. With the closest audience member being 15' away from the stage, the need for front fills is very minimal with such a narrow stage.


Evan
 

Attachments

  • Screen shot 2013-07-17 at 2.12.25 PM.png
    Screen shot 2013-07-17 at 2.12.25 PM.png
    71.6 KB · Views: 3
Re: Line Array Setup and Angle

Evan Kirkendall said:
I retract my statement from earlier. Got home, and got on my computer. Plugged in the d&b V12 in the array calc(120 degree box, about as close as I can find to your box), and I ended up with the following:

Frame to bottom box: -7 (Hopefully your frame allows this) Box -6dB
8 -6dB
6 -4dB
5 -4dB
3 0dB
2 0dB

Looks like about 6dB difference between the front and back. Probably as good as it gets with a ground stack array in this situation. With the closest audience member being 15' away from the stage, the need for front fills is very minimal with such a narrow stage.


Evan
Click to expand...

Thanks Evan. That's a huge help to me.
 
Re: Line Array Setup and Angle

Bennett Prescott said:
Nick, just repeat the lazy system guy's mantra: Never use zero degrees. Never use zero degrees. NEVER use ZERO degrees.
Click to expand...

Hey Bennett, can you elaborate on this? I've been stuck a few times with low hangs of 6 boxes/side and really had no choice but to have no splay between cabinets. What is the theory behind that "mantra'?
 
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.
 
Top Bottom