PA Setup Help

[wreckingcrew24]

Hey everyone new to the forum and I need a little help.

My church is having an outreach at a park and were expecting 1000-2000 people. We are having a couple of rock style bands perform and Im trying to put together an adequate PA system for the event. We will be using a Presonus studiolive 16.4.2 mixer, Behringer cx3400 2/3/4 way crossover, 3 Mackie Fr2500 amps running 4 JBL Jrx dual 15'' speakers and 2 JBL jrx 18" subs. We also have 2 JBL Prx powered 15" speakers rated at 1500 watts and 1 JBL prx 15" powered sub rated at 1500 watts.

I was wondering if I should run this all as a 2 or 3 way system? Im looking for the best possible sound and I realize I might not have enough total power to accommodate all the people but just looking to get the most out of what we have. One thing to consider is the mixer has 4 outputs and 1 mono output and all 5 can be used at the same time.

Thanks for any help

 

[JMFahey]

My church is having an outreach at a park and were expecting 1000-2000 people. We are having a couple of rock style bands perform and Im trying to put together an adequate PA system for the event. We will be using a Presonus studiolive 16.4.2 mixer, Behringer cx3400 2/3/4 way crossover, 3 Mackie Fr2500 amps running 4 JBL Jrx dual 15'' speakers and 2 JBL jrx 18" subs. We also have 2 JBL Prx powered 15" speakers rated at 1500 watts and 1 JBL prx 15" powered sub rated at 1500 watts.

Considering you do not seem very experienced, (nothing bad with that of course), and that it's a one-off event, I'd try to use what you already have and keep it simple.

You can have good sound, although not bone crushing .... but it's a Church, Family type event,so we don't need Metal Monsters festival pressure levels.

In fact and to be realistic, most people will expect SPL similar to what they get in Church, that's what they are used to.

2000 people in a park?
Ok, most will be Families, perhaps 20% will be Rockers.

You have 2 different kind people mixed there, with different needs.

All of them , will need to hear voice (preaching, prayer guidance, bingo/lottery prizes, general announcements, etc.) and "background music".

Some of them (20% ? 40% ?) will want Rock SPL and will get close to the stage.

The point is, you do not need Rock levels all over the park.

So I'd set a main system at the stage, and add some reinforcement some 50 yards from the stage, to help people who for any reason didn't get close.

If you have those power amps and nothing else, you don't have many independent amps for biamping.

Besides you'd need quite smaller ones for the HF side, so given what you have, I'd run the system as full range with help from subwoofers.

I'd use:

> 2 Mackies (4 750W/4ohms available) to run the 4 JRX215 , 2 per side, full range.
Set your limiters sensibly so as to never clip them, first for clean sound and to avoid burning horns.
For better or for worse, this is your "main" sound source.

> 1 Mackie to drive both JRK118 SW.

We have a potential problem here, the Mackies are 750W/4 ohms and the Subs are 350W RMS , also 4 ohms.
There is a very distinct possibility of blowing them unless you are very careful.
Specially outdoors where "bass is never enough"

If you have limiters which can be set so the Mackies stop at around 350/400W .... fine.
If not, I'd play it very safe and use them in series to get 8 ohms) into just 1 Mackie channel.

> use the 15"powered subwoofer to reinforce the main stage system.
You might put the 2 passive ones on one side and the active one on the other.

You will have good, although not bone crushing sound in front of the stage.

> the two powered JRH15" speakers.
Depending on the park size , more precisely the people distribution, you may either add them to the main stage system, perhaps more "open" , say some 10 yards to the sides , 5 yards forward to "spread " the sound source , cover more peple nearby, and let the sound reach naturally the rest of the park, at reduced level or , if people is spread all over the park far from the stage, you might spread them further, on poles or hanging from trees, to improve long distance sound.

The final decisions are yours, depending on meeting size and distribution.