4 extra JBL's

zac850

Well-Known Member
My school was donated 4 JBL speakers for our permeant set-up thats going up. We are in the school gym temporarily, so where ever they go needs to be out of the way, or we need to be able to move them. We have 4 other larger speakers (sorry, i don't know any specs on them) and they are going to get hung up about 8 feet above the gym floor. We currently have some 8 channel sound board.

We are also putting up green valores that we got from Radio City Music Hall, and they will go up around the gym to help absorb the sound.

anyway, where would be a good place to put these 4 JBL's? Any suggestions I should suggest to the group?

Thanks
--zac
 
It will be helpful to know the following things:

Dimensions^n. Size of stage, size of floor, location of stage on floor. Location and size of seating area.

Where are your speakers located and where are they pointing?

What are these four JBLs intended for? Theater? Music? Announcing for games?

What are the room surfaces like? It's a gym, so I'm assuming it's 99% hard wood or other hard surface everywhere.

Once we know that, it'll be easier to advise on speaker placement.
 
This may sound stupid, but my school made the error of configuring the sound system wrong the first time:

If you are using these JBL's as primary or Music program speakers: MAKE sure they have comfortable distance from the front of the stage!

Our school put em just about on line with the front of the stage, and we have somewhat traumatic feedback problems. Of Course I take lots of juice out of our JBL main mix speakers and into the side fills, but we need them there for primary support.

If you are using them as side fills (not primary, but on the sides of the auditorium) then you would pretty much just want to see that they were evenly spaced and given a good deal (25-45 degrees) of twist towards the rear of the auditorium/gym.

But yea, gym/auditorium specs would help greatly.
 
the room is the size of a basketball court, and fairly high. The walls are concrete and brick, and the floor is hard wood. The stage size varies with each set up, as it is a removable stage. For concerts it is set-up in a U shape, covering about half the basketball court, and for plays it ends up covering around, 1 quarter of the basketball court (i don't have exact measures, sorry...)

thanks
zac
 
Well, best thing you can do I think is use them as delays. It would be nice to know what model speaker they are.
What I mean is that in a room such as that, you're likely to get a high Lr/Ld ratio. This will make your critical distance very short. I'd use these speakers as delay sources in order to increse the ratio and thus have a bigger critical distance. Ths may take some calculating to do, or some hearing. One very important thing is to aim the speakers at th audience, and try to stay away from walls and hard floor. You're gonna have to come up with a general audience plan that covers most of your needs in each case. And you should see where the main 2 will be, try to get them all in line, and not end up shooting sound at 90 degrees from the other two.
A delay line will be necessary, although it can be done without it, you're gonna have phase issues.
 
Inaki2 said:
Well, best thing you can do I think is use them as delays.
What I mean is that in a room such as that, you're likely to get a high Lr/Ld ratio. This will make your critical distance very short. I'd use these speakers as delay sources in order to increse the ratio and thus have a bigger critical distance.

Ok, im a light guy, not a sound guy really. Can someone explain this in laymans terms? :D

thanks
 
Well its like this: if you put the 4 peakers up front, ten at the end of the hall all you're gonna get is reverberant sound, that is a big muddle of sound. By putting the speakrs as a delay you get more direct sound up to the rear of the hall. This would mean youhave the main 2 speakers up front, then at some distance you put 2 JBLs and some distance from these you put another 2.
 
ok, i think i understand, do you mean having the rear speakers put the sound out a secound or less after the main speakers produce the sound? I understand what you mean about the reverb sound though....

lol, i sould stick to the lighting.....

:?
 

Users who are viewing this thread

Back