T39 Spacing?

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harquahalas
Posts: 74
Joined: Thu Feb 08, 2018 12:18 pm

T39 Spacing?

#1 Post by harquahalas » Mon Jun 11, 2018 1:22 pm

Hi Everyone! I've been getting a ton of help with my piano recital hall plans on this forum. The people here are quite a valuable wealth of information. I'm including a picture of the recital room and stage I'm building and have a question about sub placement. I was originally planning to build my T-39s to fit under the stage in the center. The 2 problems I have is leaving an open space while keeping a good aesthetic, and that I would have to build my cabs at 15" width for them to fit under the stage. In the plans, I read that I want the subs together or at least 56' apart. I'm looking for alternate suggestions to putting them under the stage and if there's a good option for the room, I can make the cabs wider.

I'm thinking I could put one T-39 in the back left corner at the back of the stage. If I put the other one 56' apart and on a wall, that would put it right around where you see the office chair. The width of the room is 32' and the length of the room is 56'. It would be nice if both subs could be in the wings of the stage, but it sounds like that won't be ideal.
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Grant Bunter
Posts: 5933
Joined: Mon Nov 28, 2011 11:12 am
Location: Ilfracombe Queensland Australia
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Re: T39 Spacing?

#2 Post by Grant Bunter » Mon Jun 11, 2018 3:28 pm

It's not best practise to put a sub on stage. Don't do that! It's not nice for those playing.
Your picture shows it's also not aesthetically very good to separate subs by 56'.
Clustered together with the mouths of the subs at the the front edge is your best bet.
If 2 subs isn't enough in this position, you could add more.

Remind us again, how deep is the stage?
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...

harquahalas
Posts: 74
Joined: Thu Feb 08, 2018 12:18 pm

Re: T39 Spacing?

#3 Post by harquahalas » Mon Jun 11, 2018 3:50 pm

Stage is 15' deep and there is a 25.5" wing on both sides where there is no stage.

harquahalas
Posts: 74
Joined: Thu Feb 08, 2018 12:18 pm

Re: T39 Spacing?

#4 Post by harquahalas » Mon Jun 11, 2018 5:10 pm

Oops! Stage is 14' feet deep. 21.5" high. Under stage clearance is 15.5".

Grant Bunter
Posts: 5933
Joined: Mon Nov 28, 2011 11:12 am
Location: Ilfracombe Queensland Australia
Contact:

Re: T39 Spacing?

#5 Post by Grant Bunter » Mon Jun 11, 2018 6:17 pm

It's ok.
The mouth of the cab 14' from the rear wall is no problem...
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...

CoronaOperator
Posts: 1484
Joined: Wed Mar 25, 2009 7:07 pm
Location: Medicine Hat, Alberta, Canada

Re: T39 Spacing?

#6 Post by CoronaOperator » Mon Jun 11, 2018 6:33 pm

One of the benefits of a permanent install that you don't normally get with a mobile gig is that you have the time and access to the space to try out all possible locations. Put your subs on a dolly, grab some volunteers, order pizza and play some tunes. Some spots will drastically sound better than others, move the dolly around and dial them in.
Built:
17" width 10" driver Autotuba
2 x 29" width dual Lab12 Tuba60
6 x DR250 2510/asd1001
In progress:
2 x DR250 2510/asd1001
For best results, point the loud end of the array towards the audience

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BrentEvans
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Joined: Thu Oct 09, 2008 10:38 am
Location: Salisbury, NC

Re: T39 Spacing?

#7 Post by BrentEvans » Sat Jun 23, 2018 7:49 pm

This isn't so much about the sound here as the stage. If this is a piano recital hall, I assume you're planning on having a piano on that stage, which appears to be 2x4 frame and leg construction with a single sheet of plywood on top. From experience at many churches and in my own home... that is not enough support. To support the weight of even a small grand piano, you don't want a legs-and-frame construction. If you want a 16" high stage, it needs to be built with a 2x8 frame at 24"OC under a 2x8 frame at 90 degrees at 16" OC, double sheeted with 23/32" tongue-and-groove plywood running in opposite directions, glued at every joint of the 2x8s, along the seams of the plywood, and between the layers of sheets. Otherwise you will get squeaks and sags. My house has a sagging spot from my piano becasue of the single sheet construction and that's with floor trusses at 16" OC. I have been on a number of church stages with the squeak problem that were built like you're building that stage.

Even if you're not going to have a piano in there, that type of stage is still going to be pretty shaky. I've used similarly constructed stages a number of times, and it's not something I'd want in a portable situation, and certainly not as a permanent fixture. If its meant to be portable, do yourself a favor and buy proper portable staging.

Just trying to help you out.. please don't take it as a criticism.
99% of the time, things that aren't already being done aren't being done because they don't work. The other 1% is split evenly between fools and geniuses.

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