Sub Choice and Location

Ben Gingerich

Sophomore
Oct 19, 2012
188
0
16
Warner Robins Ga
I'm installing a new system in a gymatorium 106ft wide by 75ft deep, (seating area is only about 60ft deep) an A-frame roof 32ft high in the center and 24ft on the side it will be 2 SM80s per side with delays near the back at 21ft high, that is highest i will be able to hang on the sides due to the air ducts, but can go all the way to the top in the center. (yes a qualified rigger will be hired to fly the cabs)

My question comes in here, what sub and where to put it, my original thought was to hang a single TH212 in the middle of the room at the same trim as the outside speakers, however the center of the stage comes out and the sub would be right over the stage.
I had the thought to move it forward 4ft and delay it back to the mains so there is less LF reflections off the stage that’s 3.5ft tall. Or would multiple subs in a cardio configuration be better?

What do you suggest? They have about $4000 for subs & amps.
 
Re: Sub Choice and Location

I'm installing a new system in a gymatorium 106ft wide by 75ft deep, (seating area is only about 60ft deep) an A-frame roof 32ft high in the center and 24ft on the side it will be 2 SM80s per side with delays near the back at 21ft high, that is highest i will be able to hang on the sides due to the air ducts, but can go all the way to the top in the center. (yes a qualified rigger will be hired to fly the cabs)

My question comes in here, what sub and where to put it, my original thought was to hang a single TH212 in the middle of the room at the same trim as the outside speakers, however the center of the stage comes out and the sub would be right over the stage.
I had the thought to move it forward 4ft and delay it back to the mains so there is less LF reflections off the stage that’s 3.5ft tall. Or would multiple subs in a cardio configuration be better?

What do you suggest? They have about $4000 for subs & amps.

TH118 all the way up in the Apex of the roof. Delay the mains to coincide. The Apex of the roof will wall load the sub and the height should help even out coverage in the room. Modeling this would be best though--Danley would probably offer free insight as well if you reach out to them.

Jeff
 
Re: Sub Choice and Location

I'm installing a new system in a gymatorium 106ft wide by 75ft deep, (seating area is only about 60ft deep) an A-frame roof 32ft high in the center and 24ft on the side it will be 2 SM80s per side with delays near the back at 21ft high, that is highest i will be able to hang on the sides due to the air ducts, but can go all the way to the top in the center. (yes a qualified rigger will be hired to fly the cabs)

My question comes in here, what sub and where to put it, my original thought was to hang a single TH212 in the middle of the room at the same trim as the outside speakers, however the center of the stage comes out and the sub would be right over the stage.
I had the thought to move it forward 4ft and delay it back to the mains so there is less LF reflections off the stage that’s 3.5ft tall. Or would multiple subs in a cardio configuration be better?

What do you suggest? They have about $4000 for subs & amps.

I often move the sub out into the room-but I never delay it.

If you delay it-it will be right for the people at the back of the room and WORSE for the people near the front.

However whenever I do this I use a speaker that is more full range than the SM80-so the sub crossover is lower.

THen you don't localized to the sub, but rather to the main speakers.

In your case I would recommend the TH118 over the TH212 and put it basically in line with the mains but in the center of the mains.

Yes the timing will be "off", but when you use "stereo" mains- and subs-it is going to be off in most of the room-no matter where you put the subs.

That is the reason I ALWAYS start off with a center speaker system and try to have the sub located with it. THEN you stand a good chance for getting a real system alignment.

I would put the sub at the peak of the building-to minimize the reflections off of the ceiling and the natural A frame will help extend the horn.

Put the exit toward the peak of the A, not on the bottom as most people would do.
 
Re: Sub Choice and Location

I thought I would give an update, after normal church budget stuff, they finally ordered equipment. Went from being a center hung mono system based around the SH96HO to an L C R system to a LR system to a Mono system based around a center hung SM100F, oh well thats what pays the bills.

We went with a TH118, the church has a lift so we have some time to play with the placement a little bit. I will probably try hanging the sub out in front of the mains approximately 15ft to try and keep the reflections off the wall that's above the front of the stage. (i attached a picture to show what i mean) I will try what Jeffrey & Ivan suggested as well.
With the stage sitting "in a cave" and the speakers being 6ft in-front of that wall we will treat it with 4in & 6in acoustical panels,

Thanks guys
ccwr lip.jpg
 

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Re: Sub Choice and Location

I thought I would give an update, after normal church budget stuff, they finally ordered equipment. Went from being a center hung mono system based around the SH96HO to an L C R system to a LR system to a Mono system based around a center hung SM100F, oh well thats what pays the bills.

We went with a TH118, the church has a lift so we have some time to play with the placement a little bit. I will probably try hanging the sub out in front of the mains approximately 15ft to try and keep the reflections off the wall that's above the front of the stage. (i attached a picture to show what i mean) I will try what Jeffrey & Ivan suggested as well.
With the stage sitting "in a cave" and the speakers being 6ft in-front of that wall we will treat it with 4in & 6in acoustical panels,

Thanks guys
View attachment 12380
That's quite a budget change.

But what is really the most important-is "Does the SM100F do the job?"

Sometimes sub placement is a "guessing game". Using your "best educated guess". Sometimes there are all sorts of "Oh I hadn't planned on that".

Let's hope you get it right the first time. :)