Potential LARGE Build - Questions...

[doncolga]

They were pretty rough on you over there. What I do is not even in the same ballpark as the venue you're referring to, but I know I'm very happy with my T30's I just built.

[JDM570]

Yeah... they kinda tore me a new one on that forum lol Partly my fault because I forgot to mention that I was a 'noob' when it comes to this scale of sound

[gdougherty]

I'd have no issues going with BFM for the sound system, but if you're trying to book C and B level acts, you're not going to get away with a pair of StudioLive boards. Try an SC48, Si series or iLive and you're starting to get into the realm of what'd be acceptable. If many of those will turn their noses at an LS9, you'd have no chance with the Presonus.

I'd also hazard a guess that you're in way over your head here. What are your plans for safely rigging the DR300's? It sounds to me like you're going from a club level mindset and trying to outfit a small arena size venue. The two are vastly different worlds. Do yourself a favor and involve someone who really knows their stuff.

[doncolga]

What are your plans for safely rigging the DR300's? It sounds to me like you're going from a club level mindset and trying to outfit a small arena size venue. The two are vastly different worlds. Do yourself a favor and involve someone who really knows their stuff.

I will say that did concern me as well as I read over there. Again, something like that is totally out of my league, especially flying. Definitely would be smart to be liability conscious as a safety point.

[JDM570]

As far as safety rigging... the DR300s would be permanently fixed to the 12" wide/thick support beams that hold the building up... if those give... the speakers falling are going to be their last concern lol in addition, safety cables would be ran from each cabinet to the overhead horizontal beam to as an extra measure. Inside the DR300 cabinets, the internal bracking would include internal mounts for bolting to (metal)

I would love to go with a SC48... but... if the venue had the kind of capital it takes to spend $25,000+ on just the mixing console, the probably would be ok with going ahead and spending $10,000/piece of Pro Manufactured speakers, rather than considering custom built. They are only looking to book 2-3 possibly 4 national acts per year - rest of the time it's larger name local bands and such. This is a relatively rural area - so there isn't enough population withing a radius of 100 miles to even warrant trying to book any current big-name bands. They're looking to book bands that can pull a crowd of 2,000-3,000 people - and I don't think those level of bands are going to expect a $25K+ mixer to be waiting for them lol (think bands that were somewhat well known - but are well past their prime awhile ago)

I do agree in regards to involving people that have more working knowledge... hence why I'm talking to you guys . There isn't anyone locally that would really be of any help in this situation. My goal here is to outfit them with the best sound system their budget will allow. "best bang for buck" basically

[Gregory East]

Sounds like a whole lot of people are "out of their depth" but it's all do-able. Go nuts. I'm no expert but a couple of points that may not have been addressed:

The venue will need local area authority permission to go ahead.
Even with DR's I think you'll need centre fill for the front.

There isn't a great deal of posting on super large BFM systems aside from when one of the builders does one for a third party. Some of the guys have a lot of experience running other large rigs though.

Oh, yeah, Bill has been known to offer his services at very reasonable rate to tune in such a system once it's been built. Your locale my not have the same appeal to travel though

[JDM570]

Any recommendations regarding center fill?

[SeisTres]

With this being said... any pointers on 'selling' the investor on why it would be better to go with the BFM Cabs -vs- Professional Manufactured? (Other than the obvious HUGE amount of $$$$ it would save him.)

Simple. These cabs were specifically designed for the exact purpose you will need them: big pro sound set up. And usually, DIY means someone just cooking up a half-assed idea and running with it. However, in this situation you will be building cab actually designed by an acoustic engineer (a real engineer, not the technicians who call them selves "engineers") with field experience. So in reality, it would be like taking apart a manufactured speaker (which involves R&D) and simply building the exact thing yourself. Remember to point out that you're just going to be the builder and the design has already been tested to meet specifications by the designer.

If you look at an assembly line of the big manufactures, they do exactly what one is able to do with these plans. They cut the wood, make all the cutout, put the cab together, finish it, paint it/cover it, line it, and load it with the crossover and drivers. Don't know if all the manufactures actually test the final product, in the video I saw, they do. Of course, one also tests the final product and compares it to the published charts.

If everything does go the way you plan, I think the best way to provide figures when certain acts specify certain things is not to provide numbers at all but have factual spl charts of the system once installed. If they cannot read them, then they have no business being a sound "engineer".

[Tom Smit]

Think there would be any issue regarding vibration from 8xTuba 60's under the stage? (in regards to vibration going through to the band that's playing)

If so, is there a way to lessen the vibration that's going up through the stage floor? (floor is wood btw)

There will be no vibration from the walls of the cabs, only possibly from the low freqs.

BTW, welcome!

[Bill Fitzmaurice]

Any recommendations regarding center fill?

OTop 12s will suffice, 10 to 20 feet apart on the front of the stage. You'll need W10s also, perhaps eight of those.

[JDM570]

Got a rough estimate of the size of the audience area at this venue... The width of the stage is about 40', and the audience area is roughly 100' long. The stage is enclosed on 3 sides, and the audience area has a roof, but no walls (just support beams for the roof).

With this being said, what's your opinion on the placement of the DR300's (and possibly OTop 12's) to get the most even coverage? Was originally planning on running 4 DR300's mounted near the rafters on each side of the stage. But, given the length of the venue, wondering if it wouldn't be better to do a delay-line, and have 2L 2R DR300's where I'd originally planned, and then a set at 35' and another at 70'?

[Tom Smit]

Given the area size my thoughts would be to use the DR250, or maybe the DR280 instead of the DR300. Still use line array, four per side, but the bottom two cabs on each side would be melded array. My reasoning is because the area is only one hundred feet deep.

[Bill Fitzmaurice]

Got a rough estimate of the size of the audience area at this venue... The width of the stage is about 40', and the audience area is roughly 100' long. The stage is enclosed on 3 sides, and the audience area has a roof, but no walls (just support beams for the roof).

With this being said, what's your opinion on the placement of the DR300's (and possibly OTop 12's) to get the most even coverage? Was originally planning on running 4 DR300's mounted near the rafters on each side of the stage. But, given the length of the venue, wondering if it wouldn't be better to do a delay-line, and have 2L 2R DR300's where I'd originally planned, and then a set at 35' and another at 70'?

Where line arrays are concerned a 100' throw is a walk in the park. You don't need remote towers less than 250-300 feet out. Your original plan is fine.

[sine143]

how about 8 36" wide T48s under the stage (2 vstacks, 4 in each, then coupled together as demonstrated underneath) a

"You can go wider too, stacking eight cabs in a 2x/2x (or four cabs in a 1x/2x) stack as shown here.



With T48s the spread between the two sets of mouths means they'll couple only below 100Hz, so you need to crossover at 100 Hz or lower. T39s laid out this will can crossover as high as 125Hz."

Or you could 12 27" wide t48s, stacked in the same fashion cept 3 tall. 2k people outdoors seems like it might call for a little more headroom on the subs, and the 20 foot minimum audience distance might mean the 300s will be choppin heads off maybe (although I'm sure powershading will take care of that.) Idk if the 300s will have the requisite hf dispersion, perhaps the 280s (maybe 5-6 per side, flat arrays on top, melded on bottom) will be better?

[Ron K]

And you're correct about the twelves, they're not horn loaded. Rather it's closer to a bandpass configuration. You can't compare charts, as EAW doesn't publish any for the 760 series. But they do give the LF sensitivity as 96dB.

The rear of the 12's are in a horn throat configuration similar to the old keels design.If you look closely you can see the pieces of wood forming the throat section above each driver at the back.

Here's a better view.



Also since the box is shorter in the back vs the front that would complete the horn loading the path length down the side of the box. If you look at the box from the side the front is about 1.5" higher then the back. Sorry to disagree but the 12's are indeed horn loaded.