Question on adding more speakers

klarkkentster

I currently run 2 qsc k-12's and K-sub. Our room is weird pie shaped and I seem to have lots of empty spaces when walking around listening to the sound. I am thinking about adding our old SRM-450's to the room.

1. Should I just piggy back off the k-12's? Or run dual mono on the Drive rack and use k-12's off one side of the rack and SRM's off another.

Anybody have any recommendations of placement? I hope i'm making sense. I am a volunteer running sound at our church and obviously lack professional knowledge.

One option I have is: k=k12 and S = SRM.

KS Sub SK OR K S SUB S K




Crowd Crowd

Dra

Pie-shaped? Can you be a little more specific? Maybe post a drawing of the shape and with dimensions?

DRA

klarkkentster

I'm uploading very crude drawings.

It's in a high school forum. Raised stage. Thanks a bunch for your time

klarkkentster

it's a high school forum. Raised stage seats maybe 250 low ceiling in the back



Thank you for your time

Gadget

The "A" position would require delay you don't have, and "B" you would be overlapping coverage...and causing issues with phasing and sonic anomalies...

Unless you flew the JBL's (B/C area) and used the K10's as simple front fills...THAT might work...

Dra

Also, Use the nicer sounding speakers for mains. Set them so the dispersion of the horn goes right down the side walls (not bouncing off the walls).
The K12's are 75 deg so maybe those.
Then try adding a single SRM (90 deg) on the floor (or raised to the height of the stage(top of box)). This speaker would only be "whispering" in comparison. Just to add presence. Might require both, but one might do.

DRA

Dra

You can make a visual guide to help aim then using a yard stick (or anything long, straight and light) and a protractor. This will give you a rough estimation.

I laid out you K12's pattern (75 deg) in AutoCad and moved them 25 feet apart.
With both cabs facing straight ahead (for example) the horns intersect at approx 16 feet. Opposite angle of dispersion is 37.5 degs outside perpendicularity.
Turning each cab in 15 degs, they intersect at 9 feet. When doing that, the opposite angle of the dispersion is 23 degs outside perpendicularity.
Turning each cab in 30 degs, they intersect at 5 feet. (I can't imagine anyone closer than 5 ft from the stage.) When doing that, the opposite angle of the dispersion is 8 degs outside perpendicularity.

@ 35' spacing with same angles:
Intersect at...
22'
13'
7'

This may give you enough "science" to figure out you best starting point. Remember though, that sound and numbers sometimes don't agree.

With a real room layout (rough dimensional), including stage, I could make a much better config guess. The key is really the side wall angles and their relationship to the stage edge / speaker location. I use this method all the time when prepping for my corporate type events that typically are in hotel ballrooms in distant cities.


DRA

klarkkentster

Thanks for everyone's input. I will try and get some accurate measurements and pics on Sunday. Wanted to add another piece of the puzzle and another question.

We are using a Presonus 16.4.2 board and have the studio live software so i could use the delay wizard if i need to put speakers farther back that the mains. Just a thought.


Dra - is there an ideal intersect point?

As suggested:
I could add one on top of the sub with the pole and adjust using the gain to get proper fill. I'm not sure I can place directly in the middle due to the fixed projector screen in the room.
Any idea what a safe distance apart I could place the speakers apart without causing negative sound anomalies?

I'm wondering if I hug the projector screen with the SRM's - (one on the sub...one on a lowered speaker stand. And them place the QSC about 8 feet away from them.

I'll add a couple pics that may help...but wont have more info till Sundays service. (we are a portable church)

If there are measurements that are more important than others..pleas let me know. thanks.

klarkkentster

This is a pic prior to purchasing the new system. We had the SRM's farther out (as pictured).


K-12's are now placed between the screen and the music stand you see pictured,

Dra

You said this for "for" a church, but "in" a school. What are you saying? That you have to set this up for every Sunday?

As for a perfect intersection point... in reality no intersection is best when it comes to the same output reaching an ear at different times. Stereo content (true L&R) is different, but what are you gonna do? Can't have both.
You don't have the gear to worry too much about that. You have to choose between good sound in spots and no coverage in others, or be limited by the overlapped fields and realize that you get the best average sound you can get.
The center fill I mentioned is the speaker BELOW stage level firing right into the audience.

DRA

Dra

You have yet to tell us what the function of the PA is. Movie night. Live music. Preaching with a lavalier mic. ??? Your answer might change everything.

DRA

klarkkentster

We play canned music from I-tunes and 3-4 live tunes with:
3- vocals
1 - Piano
1- Cajon
2 guitars

and then Pastor uses wireless mic to Preach with

Dra

From the stage or floor? Behind the curtain?

DRA

klarkkentster

Sorry. It all happens from the floor. School doesn't allow us to be up on the stage.