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[Gary Creely]

Rich,

If you are going to replace the speakers I would at least have an EQ in the package, if the budget allows go with a dsp. I am not sure what the reflective surfaces and DSP have to do with each other, but you can solve a lot of issues with good dsp.

Do not set it by ear. If you are going to set it by ear I would suggest not using one at all. If you have a company do it the should rta the system as part of the deal.

[Brad Weber]

What a mix of good suggestions and comments apparently overlooked!

Moving the speakers forward to be at or in front of the front edge of the stage will certainly help.  Not only will it get the stage itself out of the pattern, but it will reduce issues due to reflections off the wall currently just behind the speakers and will get them much closer to the congregation, allowing you to turn down the volume.

Do you mix mono or stereo?  If mono, you might try one speaker covering each seating area, the forward corners of the stage look to be in about the right positions for that.  If stereo, you will have to turn the speakers aimed in so that each covers the entire seating as evenly as possible.  Another thought for mono mixing might be to try just one speaker located about where they currently are in Section (maybe closer to the wall behind them), but centered.  This will probably still greatly limit gain from mics on stage, but might help with the mics off stage left and eliminating interaction between the two speakers.

Think about some acoustical treatments for the rear wall and perhaps even ceiling (it looks like you could be getting some interesting reflections off the ceiling) rather than trying to band-aid the results with audio equipment.  Much better to eliminate problems that to try to overcome them.

Having all the EQ faders down 8dB is the same as turning down the system 8dB, but with some negative effects thrown in for free.  Try turning down the amp(s) and pushing the EQ faders back up.

Which brings up the fact that you mentioned there being two amplifiers.  Are they both used?  Can you tell us how they are wired?  Are the speakers bi-amped or are there subwoofers or perhaps ancillary speakers somewhere else?

A 1/3 octave equalizer would be better than the 2/3 octave you have now.  A parametric EQ or DSP would be even better.  However, unless you are familiar with using these or hire a qualified person to do the system tuning, you might not get that much more out of it.  It sounds like you are not locked into doing this all at once.  I would try getting the most out of what you have before buying a different EQ or anything like that.  Getting the speakers better located and aimed, perhaps treating the rear wall and adjusting the system you have for proper gain structure will benefit you no matter what you then do for signal processing.  You may find that you are satisfied with the system at that point or may get enough improvement that the church decides to invest more money in it.

[Ira White]

Ivan Beaver wrote on Fri, 15 June 2007 16:31

So how is a DSP better than a 31 band because of reflective surfaces?

I actually meant either choice was necessary due to the reflective surfaces, but I see where the syntax could be taken either way. However, DSP tends to be more precise than the average 31-band unless you're purchasing an expensive high-end model, and the DSP option would offer more flexibility in the future if the system expands in any way.

[Ivan Beaver]

I am still failing to see what differance an eq will make in a room with reflective surfaces vs one that is dead?

The only way you can eq a room is with a wrecking ball or bulldozer.

[Rich Stevens]

Brad Weber wrote on Sat, 16 June 2007 03:52

Getting the speakers better located and aimed, perhaps treating the rear wall and adjusting the system you have for proper gain structure will benefit you no matter what you then do for signal processing.  You may find that you are satisfied with the system at that point or may get enough improvement that the church decides to invest more money in it.

I agree.  I'm going to try to improve the positions of the current speakers as a stop-gap measure and I'm sure it will give a big step in the right direction.  Unfortunately, any position is going to be a compromise unless we fly them, and I'm not going to recommend we fly the Carvins - they simply weren't designed for it. That's why the concentration on new speakers, and the EQ or DSP that would have to come with them.

[Brad Weber]

Rich,

Big picture, what is your experience with audio system design, wiring practices, setting system gain, programming DSPs, system tuning, etc.?  What relevant tools do you have?  Might you end up buying the main equipment yourself but have pros hang the speakers, wire the system and adjust and tune the system?  And after that, then have no system warranty, documentation, etc.?  If so, then there may be advantages to simply hiring a pro to do it all, including design, and provide you documentation, warranty their work and so on.  You might find this, http://www.audiosystemsgroup.com/3Times.pdf, interesting reading.

Flying speakers in that space looks like it could be an interesting challenge.  Based on your drawing, it looks like they might have to be dropped down quite a bit to be in an effective location.  And a center cluster at the front of the stage would have to have very wide coverage, an arrangement for which it can be difficult to get even coverage over the seating.  Then there are all the practical considerations such as whether the speakers might block sightlines to some important element or cast shadows or interfere with ductwork or diffusers.

As far as what speakers and whether subs might be appropriate, more on what you do would help.  It looks like you have a band but it is also a fairly small room, so do you mic everything or only certain instruments?  Is it a high level 'energetic' service?  Do you have wireless mics and people that tend to move around a lot when using the mic?  If you mic the kick, DI the bass, etc. then one or more subs might be appropriate, but that also introduces a crossover and more system tuning into the picture and thus makes the installation and tuning more complex.

Since you identified a center cluster, I'm assuming that a mono mix is possible.  Would it be feasible to temporarily sit just one of the Carvin's on the brick wall at the center of the room with it aimed down the center of the room at the last row of seating and then sending signal to just that one speaker?  You might have to have someone hold the speaker to test this, but it could get some improvements and emulate a step towards what a center cluster would do (not saying it would be the same, just an interim step between what you have and a center cluster).  It is also a location that could probably be made more permanent if it does provide significant improvements.

[Rich Stevens]

Big picture, I have substantial experience, but mostly with portable (i.e bar band) systems and 20 years out of date.  No DSP experience - I was away having a family while they were being invented.  I'm an electrical engineer by profession, was an electrician before that, and have put together several systems for my own band and others over the years, and was known to be a pretty good mixer when I wasn't playing guitar. So, most of the equipment and wiring doesn't bother me.  My weak areas are new technology (DSP) and the finer points of speaker design/placement in permanent installations.

If we fly speakers, admittedly they will be waaaaay up.  The peak is about 32 ft high and there is a line-of-sight issue.  There is   a circular stained-glass window in the front wall, above the altar - it's top is at 26 ft off the floor, so any flown cluster would have to be above that.  No ductwork problems, but good point about casting shadows - I'll have to check possible locations against the lighting.

Our music is not exactly high-energy.  It's usually 2 or 3 guitars: one electric, one acoustic, and one who switches back and forth.  Acoustics go direct, the other guitarist uses a modeler direct.  Mine is the only amp on stage - a Fender Champ putting out a more-than-sufficient 6 watts. We run the bass through the PA, mostly because there is no stage amp.  We do not presently mike drums.  The musicians do not move around, we just stand in front of out mikes and play and sing.

We do mix in mono.  We can't move a single speaker to the center of the top of the wall - not shown on the drawing there is a large cross on the wall that sticks up about 6 ft above the top. So, if speakers are going on the top of the wall, they'll most likely need to be at the outboard ends.  I think they'd have to be pointed inward to keep away from the band - won't that cause cancellation problems in seats where people can hear both speakers?  The brick wall is still a bit farther back than I'd like - better than where they are now, but still behind most of the mikes.

[Rich Stevens]

Brad got me thinking "what if" we tried some of the fast, cheap, and easy solutions.  Like, what if we just move the cabs forward, and atop the wall?  It's bound to be better than pointing them at the wall.

Something like this:

[Rich Stevens]

...and here's the elevation.


I assume this is a lot better, just due to the fact that it improves directional control.  The cabs at least have a straight shot at the congregation (without first bouncing off the ceiling and walls) and mostly avoid the band and altar.

Is crossing the cabs toward the center a bad thing?

[Mike Sessler]

You may get better coverage, but your gain before feedback will almost surely go down. Like others have said, you need to get the speakers in front of the stage. Start with that and work up from there...

[ProSoundWeb Community]