PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

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Mkulu
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Location: Durban,South Africa.

PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

#1 Post by Mkulu » Sat Feb 04, 2017 10:15 am

400 to 500 people.
Indoor Venue, size varies but mostly around 1000 m2 length about 35 meters.
OT15 either side, cross firing.
SLA PRO are 8 of 2x6 inch driver cabs and are suspended above evenly across the stage.
T39's in a wall corner or centrally in front of the stage.
What do you guys think , especially with the SLA and OT15 mix?

Bruce Weldy
Posts: 6187
Joined: Fri Nov 27, 2009 11:37 am
Location: New Braunfels, TX

Re: PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

#2 Post by Bruce Weldy » Sat Feb 04, 2017 11:08 am

Mkulu wrote:e.
What do you guys think , especially with the SLA and OT15 mix?
Absolutely the wrong thing to do.

Do NOT mix speaker cabinets, except in cases of delay towers.

If you are doing something that large, build a bunch of OT12s or DRs. Hanging a bunch of SLAs side by side is just creating comb-filtering and loses all the advantages of stacking drivers.

6 - T39 4-25" 2-22" 3012LF
4 - OT12 2512 Melded/NSD2005
1 - T24
2 - XF210


"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."

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Mkulu
Posts: 121
Joined: Tue Aug 19, 2014 9:46 am
Location: Durban,South Africa.

Re: PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

#3 Post by Mkulu » Sat Feb 04, 2017 12:45 pm

Bruce Weldy wrote:
Mkulu wrote:e.
What do you guys think , especially with the SLA and OT15 mix?
Absolutely the wrong thing to do.

Do NOT mix speaker cabinets, except in cases of delay towers.

If you are doing something that large, build a bunch of OT12s or DRs. Hanging a bunch of SLAs side by side is just creating comb-filtering and loses all the advantages of stacking drivers.
Thanks Bruce
Funny how these things work.
So it's either one or the other.
SLA with subs or OT15 or 12's with subs.
Your preference is the OT 12 or DR's, remember I have all these 15" drivers lurking around and they do perform.Will be measuring and creating SPL charts as soon as I get the time to do it, but am positive they will do the job in the OT 15's.

Bruce Weldy
Posts: 6187
Joined: Fri Nov 27, 2009 11:37 am
Location: New Braunfels, TX

Re: PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

#4 Post by Bruce Weldy » Sat Feb 04, 2017 6:44 pm

Mkulu wrote: So it's either one or the other.
Yep
Your preference is the OT 12 or DR's, .
It's not so much preference as using the right tool for the job.

remember I have all these 15" drivers lurking around and they do perform.

am positive they will do the job in the OT 15's
You have no idea how they will perform in any BFM design without T/S specs. Just because a driver is kick-ass in a direct radiator does not mean it will work well in a horn-loaded cabinet. There is a reason that there are so many different speakers - different cabinet designs require different driver specs.....and different drivers require different cabinet specs.

Bill designed these cabs and knows what specs are necessary for them to work well, he then finds drivers that meet those specs and puts 'em in the plans along with the specs so you can try to find others that work is the suggested ones aren't available.

It is a crap-shoot as to whether your drivers will work. They must have a rising mid-range if you are using the piezo arrays. They must not be too deep or they will not fit in the cab, etc.

There's way more to it than just the diameter of the driver.

6 - T39 4-25" 2-22" 3012LF
4 - OT12 2512 Melded/NSD2005
1 - T24
2 - XF210


"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."

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Mkulu
Posts: 121
Joined: Tue Aug 19, 2014 9:46 am
Location: Durban,South Africa.

Re: PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

#5 Post by Mkulu » Sat Feb 04, 2017 9:24 pm

Bruce Weldy wrote:
Mkulu wrote: So it's either one or the other.
Yep
Your preference is the OT 12 or DR's, .
It's not so much preference as using the right tool for the job.

remember I have all these 15" drivers lurking around and they do perform.

am positive they will do the job in the OT 15's
You have no idea how they will perform in any BFM design without T/S specs. Just because a driver is kick-ass in a direct radiator does not mean it will work well in a horn-loaded cabinet. There is a reason that there are so many different speakers - different cabinet designs require different driver specs.....and different drivers require different cabinet specs.

Bill designed these cabs and knows what specs are necessary for them to work well, he then finds drivers that meet those specs and puts 'em in the plans along with the specs so you can try to find others that work is the suggested ones aren't available.

It is a crap-shoot as to whether your drivers will work. They must have a rising mid-range if you are using the piezo arrays. They must not be too deep or they will not fit in the cab, etc.

There's way more to it than just the diameter of the driver.
Thanks again Bruce
There is a lot of how to measure T/S on the net.So I better get on with it.
The drivers will fit into the OT15 taking into consideration the measurements of Bills Cab and the dimensions of the driver.I have lots of time on my hands and the necessary tools and software,so I will give it a go. :)

boatalec
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Joined: Mon Jul 27, 2009 8:36 am
Location: Long Island, NY

Re: PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

#6 Post by boatalec » Tue Apr 25, 2017 3:01 pm

In the interim you could stack the SLA's to create a semblance of an array. But end of day, the OT12's rule.

Alec

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dswpro
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Re: PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

#7 Post by dswpro » Tue Apr 25, 2017 4:21 pm

Would 4x 2 driver SLA cabs stacked per side in a single column give one OT15 per side a run for the money?
I don't see SPL curves on the SLA.

Grant Bunter
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Location: Ilfracombe Queensland Australia
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Re: PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

#8 Post by Grant Bunter » Tue Apr 25, 2017 4:43 pm

Mkulu wrote:400 to 500 people.
Indoor Venue, size varies but mostly around 1000 m2 length about 35 meters.
OT15 either side, cross firing.
SLA PRO are 8 of 2x6 inch driver cabs and are suspended above evenly across the stage.
T39's in a wall corner or centrally in front of the stage.
What do you guys think , especially with the SLA and OT15 mix?
It's already been said "Don't mix different cabs types".
Not just in this thread of yours, but also in this thread of yours:
http://billfitzmaurice.info/forum/viewt ... =2&t=24147

Are you struggling with understanding why you shouldn't?
Can we help you understand better?

Other than that, 2 x T39's will most likely not be enough, with as many tops/mains you are thinking of using...
Built:
DR 250: x 2 (melded array) with March 2012 plans.
T39's: 4 x 20" BP102 , 2 x 28" 3012lf.
WH8: x 3 with melded array.
Bunter's Audio and Lighting "like"s would be most appreciated...

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Mkulu
Posts: 121
Joined: Tue Aug 19, 2014 9:46 am
Location: Durban,South Africa.

Re: PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

#9 Post by Mkulu » Tue Jun 13, 2017 12:55 pm

Grant Bunter wrote:
Mkulu wrote:400 to 500 people.
Indoor Venue, size varies but mostly around 1000 m2 length about 35 meters.
OT15 either side, cross firing.
SLA PRO are 8 of 2x6 inch driver cabs and are suspended above evenly across the stage.
T39's in a wall corner or centrally in front of the stage.
What do you guys think , especially with the SLA and OT15 mix?
It's already been said "Don't mix different cabs types".
Not just in this thread of yours, but also in this thread of yours:
http://billfitzmaurice.info/forum/viewt ... =2&t=24147

Are you struggling with understanding why you shouldn't?
Can we help you understand better?

Other than that, 2 x T39's will most likely not be enough, with as many tops/mains you are thinking of using...
Hey Bruce I fully understand it was just a thought.
Direct radiating are another story.

Bruce Weldy
Posts: 6187
Joined: Fri Nov 27, 2009 11:37 am
Location: New Braunfels, TX

Re: PA rig OT 15 x 2 and 8x SLA Pro and sub T39 x2

#10 Post by Bruce Weldy » Tue Jun 13, 2017 1:52 pm

Mkulu wrote:
Grant Bunter wrote:
Mkulu wrote:400 to 500 people.
Indoor Venue, size varies but mostly around 1000 m2 length about 35 meters.
OT15 either side, cross firing.
SLA PRO are 8 of 2x6 inch driver cabs and are suspended above evenly across the stage.
T39's in a wall corner or centrally in front of the stage.
What do you guys think , especially with the SLA and OT15 mix?
It's already been said "Don't mix different cabs types".
Not just in this thread of yours, but also in this thread of yours:
http://billfitzmaurice.info/forum/viewt ... =2&t=24147

Are you struggling with understanding why you shouldn't?
Can we help you understand better?

Other than that, 2 x T39's will most likely not be enough, with as many tops/mains you are thinking of using...
Hey Bruce I fully understand it was just a thought.
Direct radiating are another story.
That's Grant busting your chops, not me. :mrgreen:

6 - T39 4-25" 2-22" 3012LF
4 - OT12 2512 Melded/NSD2005
1 - T24
2 - XF210


"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."

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