Reverbant room PA set up troubleshoot

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kenoir

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Dear guys:

I'm going to set up a PA system in a room with walls and glass windows all sourrounded. It's size it about 2/3 of a standard basketball ground (only 2/3 of the area for players to play the sport, not the whole arena). It have it's roof hollowed which allow the sound to go from the first floor of this room pass through without any problem.

Speakers include 15" FOH 400W 8ohm x 2, 12" plastic case 200 watt floor monitor x 4, 18" 450watt 8 ohm subwoofer x 1.

I have 1 amp to push the 4 monitors, 1 amp to push the sub, and 1 amp to push the house.

Here comes the problem.

When I first try to do some pre checking before the show, I found out the drum is as loud as usual (or louder than placing it outdoor). However, added up with the natural room reverb, the whole set can not sound clearer except the 2 crash cymbals.

And now which of the below solution should I choose? (or non of the solution below tend to make things better?)

1
Will it make sense if I strive to look for a balanced loudness by mic up more instruments and amplify them with the speakers so to cover the loudness of the drum?

2
should I only amplify the vocal's voice?

3
Use EQ to acquire only the frequency needed to make the natural reverb harmonize with the FOH?

If 2 is the answer, can I look for something that I can try micing up to improve the sound in this room?

If 3 is the answer, wht should I cut? Is it correct to not mic the cymbals because in this room it already have enough high frequency bouncing around? And I should pay my attention to sculture the mid and low frequency with the speakers?

I might have some idea (or may be nothing sounds riught from me) but just need some clarification from some expirienced people. Since in my country it's hard to get in touch with them as I just started out doing the job as a volunteer.

Every advce will be greatfully appreciated!

Thanks

Ken
 
Keep the least amount of instruments possible in the pa and monitors. Vocals only? Every mutli-path/multi-time source is another source of splash and blur.
Try to have everyone play as clean, simple, direct and as possible.
Try to have everyone avoid the temptation of over power the reverb with more volume and excentuate their dynamics. Get in, then get out of the way of the next point of focus.
Good luck. ;)

Oh. Don't throw rocks. :D
 
Think of having the perfomance as a soft acoustic version! Only vocals and soft acoustic instruments in the PA.
Those kind of rooms are really hard to pump acoustic energy into without having something like mobile acoustic absorbers placed around the room to tame the reverb.

Good luck!
 
The posts above are good workarounds. The only real solution is sound treatment of the room but that will be very expensive. If this is for a live show when the room is full of people that will help to kill some of the echo.
 
TexRoadkill said:
The posts above are good workarounds. The only real solution is sound treatment of the room but that will be very expensive. If this is for a live show when the room is full of people that will help to kill some of the echo.
Click to expand...


Thanks, I more or less got the idea of it now.

Either there's enough amount of people to kill those reverbs, :)
or
me and the audience will get killed by the reverb :(

ken
 
They are no JBLs or EVs. Just a Brand under ody-pro name "I-Max" at www.imax.com

With the spec it says -

15" 2 way
norminal coverrage 90 x 90 (degree)
sensitivity (1W/1M) 103dB
power handling 800W

will this coverrage angle contribute to the problem??

Thx a lot for the reply!

p.s.
My speaker's product page - http://www.imaxaudio.com/loudspeakers/wx.htm#wx12a (hope the link works)
 
Off Topic...

Just one off topic question (well, sort of)... How exactly are you powering four monitors with one power amp? I'm assuming daisy chaining? I'm new at this and it just seemed a bit bizzare to me.
 
sdsilenced said:
Just one off topic question (well, sort of)... How exactly are you powering four monitors with one power amp? I'm assuming daisy chaining? I'm new at this and it just seemed a bit bizzare to me.
Click to expand...

I guess I won't be a lot more expirience then you do.

But we do it like this -

Switching the amp to Bridge mono mode, then on each channel's output, we plug into the first speaker of the chain, then a jack out from the first speaker of the chain to the second speaker.

or the other way is to keep the mode in stereo, but, pan the channels you need all the way right or all the way left

With limited gears, that's how we do.

May be we will screw up things in this way, but we just want to give it a try :o

Ken
 
sdsilenced said:
Just one off topic question (well, sort of)... How exactly are you powering four monitors with one power amp? I'm assuming daisy chaining? I'm new at this and it just seemed a bit bizzare to me.
Click to expand...

Monitors are commonly daisy-chained. That makes a parallel connection, so you need to watch the impedance. If you chain four 16 ohm wedges, that's 4 ohms total. Four 8 ohm wedges makes 2 ohms, so check your wedges and your power amp's rating.

I would be a little careful about bridging the amp and feeding 4 wedges, because bridging an amp can result in a higher ohm limit. If your amp can't do 2 or 4 ohms bridged, or whatever you need for your wedges, you might be able to split them 2 and 2 on each amp channel unbridged, and stay within the amp's specs. You will give up some wattage, but then your amp won't melt :eek:
 
So, if i had 2 wedges each with 8 ohms, what would I need? This is sort of hard to understand. It seems like I use the number of speakers to divide the ohm load? For instance, two 8 ohms speakers makes 4 ohms? I think I'm making sense of this.
 
sdsilenced said:
.. For instance, two 8 ohms speakers makes 4 ohms? I think I'm making sense of this.
Click to expand...
Just to be clear, not exactly the number 'speakers, but the ohms of each cab, which is the total for a given box.
 
sdsilenced said:
So, if i had 2 wedges each with 8 ohms, what would I need? This is sort of hard to understand. It seems like I use the number of speakers to divide the ohm load? For instance, two 8 ohms speakers makes 4 ohms? I think I'm making sense of this.
Click to expand...

If all the cabs are the same impedance, yes. If you are mixing impedances (which ordinarily you wouldn't want to do), the formula is Itotal = 1/(1/Ia + 1/Ib + 1/Ic . . .)
 
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