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[Garry Wilson]

I've been doing an outdoor gig for a few years now using (6) JBL SRX718s. This is what the budget allows, previously it was 4. Also, when I initially went to 6 subs, I had 3 per side, then changed to option A, it seemed to work out better.

I'm considering changing the placement. Currently, it's two placed vertically per side and two in the middle side by side. I've attached a document.

Your thoughts please on the A, B C options. I using option A now.


Garry

[Matt Vivlamore]

I've been doing an outdoor gig for a few years now using (6) JBL SRX718s. This is what the budget allows, previously it was 4. Also, when I initially went to 6 subs, I had 3 per side, then changed to option A, it seemed to work out better.

I'm considering changing the placement. Currently, it's two placed vertically per side and two in the middle side by side. I've attached a document.

Your thoughts please on the A, B C options. I using option A now.


Garry

If you have a stage, I'd go with C.  But without a stage, then A.

[Garry Wilson]

If you have a stage, I'd go with C.  But without a stage, then A.

Hey Matt, good to hear from you.

Yes, there is a stage (flatbed trailer).

[Brian Bolly]

You will have minimal difference between Option B (2x3) and Option C (1x6) in terms of coverage and level — as the sources are grouped, these will give you the most even coverage overall.  The only thing that Option C offers is the ability to (minimally) delay-arc the boxes to widen the coverage pattern, but also requires 3 drive channels to do so.  The subs could also be spaced a bit.

With Option A, the spacing between L/C and R/C will dictate where your cancellations lie.  There could easily be a >10 dB variance in level at +/- 30 feet off axis of the center line.

The answer of "which is better" depend on what your needs are - width of coverage, depth of coverage, level at a desired listening point, and audience geometry.

[Helge A Bentsen]

I prefer A for less crossover distortion between subs and mains, ASSuming that the mains are close to the outer subs.
C (if done right) usually gives more even coverage in the sub range, but distance to mains will be a problem. How much of a problem depends on a lot of factors.

[Tim Verhoeven]

I would also go for option C. Because it allows the option to spread the array a bit, leave an equal distance between each sub. This will give you some directivity. Meaning less sub going to the sides. Depending on how wide the field/square/... you are playing on is, it allows you to send less sub to nowhere/the neighbours/...

Another comment/tip, keep the crossover area (spectrum wise) between the subs and the (low part) of the tops as small as possible. Meaning if you want a sub boost, spread the center frequencies of those crossovers.

[Caleb Dueck]

Your thoughts please on the A, B C options. I using option A now.
Garry

Here's a quick model, centered on 50Hz.  150' wide by 100' deep audience area, 3dB per color.

Option A without delay - pretty ugly. 
Option A with delaying the side stacks - less bad but still not good.
Option B - not too bad.
Option C - the sides drop in level, which may or may not be good.

Option D - delay arc, 6.5' spacing between subs - between B and C.  More even for the center, drops off on the extreme sides. 

I'd play with both B and D, and see how the 'impact' and evenness is as you walk the audience area.

[Garry Wilson]

Here's a quick model, centered on 50Hz.  150' wide by 100' deep audience area, 3dB per color.

Option A without delay - pretty ugly. 
Option A with delaying the side stacks - less bad but still not good.
Option B - not too bad.
Option C - the sides drop in level, which may or may not be good.

Option D - delay arc, 6.5' spacing between subs - between B and C.  More even for the center, drops off on the extreme sides. 

I'd play with both B and D, and see how the 'impact' and evenness is as you walk the audience area.





Thanks a lot for the graphs
glw

[Garry Wilson]

No budget for a line array. The plan is to have a pair of SRX835(s) on sticks on either side of the stage. They will be approx. 26 -28 feet apart. I'll also have a pair of SRX715 on sticks hanging off each 835, unfortunately I don't have a 2nd set of 835s. The 715s will be about 15ft away from the 835. The 835 is 60 degrees, 75 degrees for the 715. If anyone has any thoughts on the distance of the 715s, please chime in. I'm thinking about a pair of 712(s) on the stage for front fill. The audience is mainly sitting for eventual fireworks (4th of July), a DJ earlier. The audience area is on a steady uphill incline (audience seating  )

[Dave Garoutte]

No budget for a line array. The plan is to have a pair of SRX835(s) on sticks on either side of the stage. They will be approx. 26 -28 feet apart. I'll also have a pair of SRX715 on sticks hanging off each 835, unfortunately I don't have a 2nd set of 835s. The 715s will be about 15ft away from the 835. The 835 is 60 degrees, 75 degrees for the 715. If anyone has any thoughts on the distance of the 715s, please chime in. I'm thinking about a pair of 712(s) on the stage for front fill. The audience is mainly sitting for eventual fireworks (4th of July), a DJ earlier. The audience area is on a steady uphill incline (audience seating  )

I think TV was referring to the array of subs.

[ProSoundWeb Community]