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[Alex Boardman]

Well the task of designing a new sound system for my church has fallen on my shoulders.  This is due to the estimates given by professional installers that are simply too expensive for the church to rationalize as we are in a shrinking diocese.

First of all, I would never for a second discredit the work of a good sound/acoustics engineer if this were my own project, but as it is, there are really only two choices.  New system or live with the old one.  The latter really isn't an object as the audience can't hear the service very well at all.

I know that there is the possibility of designing a system that will end up being a waste of money.  Hopefully you all will be able to help me avoid that

That said I think I can do an adequate job just based on my musical (tenor sax) and extensive home theater acoustics/sound isolation experience.  I also want to learn more about live sound as I only have experienced portable band solutions.

To get an idea about what the room looks like I took some pictures (at night so they are a bit dark but I brightened them with photoshop) and I received a draft floor-plan.

Floorplan:



Pictures:

http://i45.photobucket.com/albums/f96/aboardman/Church_Befor e/

As you can see the existing sound system was "designed" for the altar to be way back on the original stage.  Right now the speakers are behind the altar as well as the podium.  As I recently equalized the room, the gain cannot be turned up very much or feedback will result.

I want to fly roughly 4-6 speakers but it would be great to have recommendations as to what kind and where I should place them to cover both the sides of the altar and the back sections.  Keep in mind the pews altogether sit roughly about 250 people.  I think the hardest part about this is coverage of all the sections.

The budget for the speakers is around 4000-5000.  This would be just the speakers.  The amps, mix etc have already been tallied for the most part.  I was thinking a simple analog mixer(mackie?- have had good experiences with those) with some nice amplifiers.  The question I have is would the church really need a subwoofer as they don't have a band but rather an instrumental chorus.  Adding a subwoofer would require   Though I am a fan of bass in the home theater

I know flying speakers is a touchy subject in this forum. but luckily there is a Cornell grad architect on the parish council who has already approved the structure for this application.

As far as acoustics are concerned I have a few ideas to deaden the room a bit to harness a bit more control over the reverb.  These are mostly taken from my ht experience so they may have no bearing her but here goes.

Point the speakers towards the ground as to avoid slapback from the walls.
Put 4x8 2"inch think rigid fiberglass panels on the side walls
Try to coat much of the rear wall space with rigid fiberglass and some of the front.
Put broadband bass trap absorbers in the corners of the room to aid in some of the present boominess.

Well, I am either a complete failure at designing or I may have a foot in the door I don't know.  I do know what musically sounds good and I am willing to learn all I can to help this congregation hear what service offers to them.

Thanks for reading as well as any comments you may make.

-Alex

[Tom Young]

What are the existing loudspeakers and why can't they be redeployed as part of a new system ?

How can the architect approve the safety of the suspension when he does not know what devices will be used and how they will be suspended ? Reviewing and "stamping" a structural design entails all of the components including the hardware, down to the nuts & bolts (literally) and also including how they are installed.

I appreciate that the church does not have 'x' amount of dollars (the amount quoted) to spare. But then saying that "we have "this" amount of dollars" has no bearing on what is required to establish reasonable intelligibility and musical clarity plus even coverage throughout the space. Good sound systems are not designed based on what a lay person says they have to spend. In almost all cases this arbitrarily chosen amount is too little money.

Implementing a poorly designed system usually means that what is being reinforced is not heard and/or understood by those who attend. This can impact how many seats are filled (why continue to attend a church where you do not clearly hear what is being preached ?).

I appreciate your desire to help. But perhaps the first task you have is to make them understand that the smaller amount of money is wasted if it will not result in a working, successful system. Another task is to convey to them that a "from the hip" declaration that the building is structurally sound is no way to ensure the rigging integrity of the new loudspeaker system and the safety provided to those who sit below the loudspeaker devices.

BTW - a well-designed sound system that is completely safe may not cost lots more than the amount you have been given.

[Alex Boardman]

Tom,

I can definitely see where you are coming from and I agree sometimes an x amount of money is not always best.  But in all honesty, anything is better than what they have now.  Flying speakers is a touchy subject and I intend to make it as safe as possible.  In all reality, the speakers shouldn't have to be flown over the pews.  As for the individual suspension rigging, I agree that there should be some inspection as well as overbuilding.

I know there is a bias to say just let a professional do it, but this isn't an option as the prices quoted are more than they could ever afford.

What I am looking for is just some advise as to what type of speakers we should use as well as where we could fly them in this position.  I think it is possible to design a system with this amount of money but bear in mind that the budget is not set in stone. This would be an estimate of what I have to spend on speakers alone.  It could even go up to 7-8 thousand.

Anyway, comments would be appreciated in any way shape or form. Even if it is over the budget, I would at least like some suggestions as to what would make for good speakers.  I need to make a plan in some form.

Thanks
-Alex

[Tom Young]

I hear you. And I guess I was ranting a small amount.

If I was going to do that space I would do one of two things:

1) re-use the existing ldspkrs (move them out in front of the mic's) and supplement them with smaller delay/fill devices (further out into the space). This all requires DSP to align the delay ldspkrs and equalize the entire system.

2) design a system based around Bose MA12 column ldspkrs (double tall) and *perhaps* with delay/fill ldspkrs. Depending on several conditions, you may not need the additional fill ldpskrs. However, you will probably need bass devices (Bose has the MB4) because the MA12's (even when double tall) cannot go lower than about 120-140Hz (depending on how loud you need them). You need double tall MA12's to achieve good directivity down to a low enough frequency.

System #2 will provide the most intelligibility because it has the greatest directivity and does not excite the room as much. This system is also easiest to install because the MA12's do not need to be (should not be) high up in elevation. But it costs more (and maybe more than you can afford).

Either system needs DSP for alignment and equalization.

If you tell me/us what your existing ldspkrs are, I/we can tell you if they're any good.

[Mac Kerr]

Alex Boardman wrote on Tue, 10 January 2006 14:07

I can definitely see where you are coming from and I agree sometimes an x amount of money is not always best.  But in all honesty, anything is better than what they have now.  Flying speakers is a touchy subject and I intend to make it as safe as possible.  In all reality, the speakers shouldn't have to be flown over the pews.  As for the individual suspension rigging, I agree that there should be some inspection as well as overbuilding.

As has often been stated in all these forums, the wrong equipment for the right price is still the wrong equipment. The same is true for installations. If you cannot afford to do the job you want, you need to scale back your expectations. As far as any rigging being "as safe as possible" there is no such thing. There is only "safe". It does not matter whether the rigging is over pews or not, it needs to be completely safe wherever it is. This means the building structure has to be sufficient, and all the rigging hardware and the speaker systems themselves have to designed for the type of rigging you will use. The installation should be approved after it is finished as well.

Mac

[Hojoon Chang]

Well, nice hall, isn't it?

You have to make a choice. 1st. typical delayed way with column speakers. 2nd. center-cluster or array for near/mid/far field solution. I recommend 2nd. one. 'Cause you can have better sound and coverage without human-made-echo.

If you can have 4 small or mini-line array, something like McCauley's IN.LINE series which not that expensive. MSRP$2000 per one, you may need at least 3. I think around 5K you can get 3 w/bumper. It may sounds overkill(800W LF/120W HF, total 132 dB SPL) but you have longer hall and it's affordable. You can find other brands like JBL, EAW.

http://www.mccauleysound.com/product_results.cfm?Family=2

[Don Cicchetti]

Alex, this is like asking a lawyer on a newsgroup for a good defense for a given case and set of circumstances.   They would have to be on dope to pretend that they could do the job right in that situation.

Get more quotes.  Tell the companies how tight money is, and most of all, stop being the "solution" here.   The pressure to fix this should not be on your shoulders.

Sound, like parking lots, plumbing, and bulletins, costs money.

Remember, the cost of bad sound done on the cheap will be added to the cost they will end up paying anyway when they get serious.

Be afraid, be very afraid.

Sorry I can't be more encouraging here, but poorly done sound is the most expensive solution of all.   This isn't about bias, it is about reality.

Don

[Alex Boardman]

Hojoon,

Would the second array provide adequate coverage for even the seating areas on the side?  The speakers mentioned are two-way but how wide would the spread pattern of sound be.  

Also, this type of array, I would think would need to be pretty far back as to provide coverage for the front middle and rear sections.  Would this be the case? If so, how would feedback related issues be solved?

I downloaded a design calculator from the manufactuer's website and I have somewhat of idea of what would happen if I ended up putting them into my design.  However the feedback issue is one I need to clear up.  Does the height of the speakers flown prevent unwanted feedback in this case scenario?  Or is the fact that directly below the speaker lies a cold spot make this arbituary?

Tom,

The existing speakers are really not very good.  Although I failed to record the brand and model, I can attest to the fact that they do not have a very good sound nor do they project well even with the microphones behind them.  Talk about a job done really poorly on an inadequate budget about 20 years ago.

You comments made about possibly using Bose speakers intrigued me.  Coming from the home theater install world it has always been a constant that Bose speakers do not perform very well given the high cost.  At times I have auditioned speakers half the price of similar Bose setups that were in a sense, twice as good.  Is live sound a different production line that Bose happens to accel in?

Thanks for all the help guys,
-Alex

[Tom Young]

"it has always been a constant that Bose speakers do not perform very well given the high cost. At times I have auditioned speakers half the price of similar Bose setups that were in a sense, twice as good. Is live sound a different production line that Bose happens to accel in?"

In the case of the MA12 column ldspkr, Bose is just about the only game in town right now. TOA makes a better and similar size column device but it costs 50% more.

Provided it is deployed appropriatley, a column ldspkr (or any line array device) can outperform a point-source system in acoustically challenging spaces. The MA12 system also exhibits a smaller footprint, easier installation and may be lower in cost.

As I mentioned, the Bose system needs bass support unless you run the level low enough that you can EQ the MA12 system to
"do" 100-120Hz (which covers the male speaking range pretty well).

[Mike Sveda]

http://www.slsloudspeakers.com/proaudio/rla_ls8695.html

[Tom Young]

How much ?

[Peter Verkerk]

Mike Sveda wrote on Wed, 11 January 2006 16:20

http://www.slsloudspeakers.com/proaudio/rla_ls8695.html

LS8695 cost: 4300,00 Euro's (in Germany...)
http://www.slsloudspeakers.com/proaudio/rla_ls8695.html

This kind of array, is the best  controllable solution (low-profile - good projection of sound)
We new here in the Netherlands: Alcons Q series: http://www.alconsaudio.com/site/q_series.html
same principles, and very, very good results.

A hanging linearray is not alway a good solution, the needed rigging hight is not always available, or wished.

[Aaron McQueen]

Quote:

The budget for the speakers is around 4000-5000.

Maybe I'm wrong but this seems like a pretty good budget for just speakers in that size room.  What does the entire system budget look like?

[Alex Boardman]

The entire budget would be a maximum of 15,000 but I want to put about 2000 of it towards improving the room's acoustics as that is an area of interest for me.

Looking at the specs on the second sls array, I saw that the frequency range was not as deep as say the mcauleys in-line series.  90 hz is somewhat low but I crossover at 80 hz on my home svs subwoofer and my system uses smaller loudspeakers than these.

If anybody has had any experience with the previous in-line array, that would be great to know as that seems to be my favorite option so far.  I have does some modeling on the manufacture's design calculator and I came up with this:

http://i45.photobucket.com/albums/f96/aboardman/Design/rough _plan_1.jpg

One thing I probably need to do is to suggest that they move the altar back as to avoid the nasty node from the unit being directly above.

Thanks,
Alex

[Ivan Beaver]

If you take this approach,how are you going to cover the first several pews, they are quite a bit down in level, you don't start picking up level untill 15' from the array.  How do you think this will look, being not very far above the people on stage heads?  Is the width of the pattern wide enough to cover the people on the sides in the front?

[Alex Boardman]

I was actually wondering about that as well.  How much db loss is acceptable for adequate coverage? The spread pattern of each speaker can go up to 120 degrees.  I see your point.  It is hard to provide coverage for the front area without moving the altar back though some feedback issues could be solved with a good equalizer?  However, from what I have read, that can muddle up the sound and decrease clarity if overused.

I would also like to hear some reccomendations for an analog mixer.  I would say the max they could spend is 2000 dollars.  I have been looking at the mackie SR series.  What is everyone's experience with these?

Thanks,
Alex

[Mark Cartwright]

Mixer wise, how many channels are you needing?  I'd recommend the Allen & Heath GL-series, like the GL2400 series.  These come in, I think, 16, 24, 32, and 40 channel boards.  I recently priced the 32 and it runs about $2500, so the smaller would be about the right price for you.

That's my input...

[Ivan Beaver]

I would second the Allen & Heath.

Regarding the dB variance, you MUST attach a freq response to that.  If you were to simply take a SPL meter and measure, it is very easy to get the same level.  The real problem is that most of the time, what you are reading is the low freq.  It is the higher freq that give the the clarity.

I shoot for +-2dB front to back-side to side.  This is not always possible, sometimes due to room construction- speaker limitations (placement-cost-visual etc), but it is my target and most of the time it is achieved.

Proper sound system design takes on many different tasks, many of which have nothing to do with actual coverage.

Of that 120* coverage-how smooth is that-actually. Have you heard the speaker and walked the pattern?  You cannot simply believe what the spec is.  You will often times find dissappointment.  Is it beamy in the middle? Does the pattern control exist for all freq or just some?

I don't mean to be so negative-but simply just sticking systems in rooms does not mean they will work properly.

Earlier this week I was at a church I went ot a church that we were asked to bid on a little over a year ago.  We would not bid the system as "designed" because we told the church it would not work and gave them models to prove so.  They didn't believe us and went with the existing plan.  When I listened to it, the models were right.  They were not happy with many areas of the sound.  This was not a cheap system and the one we proposed was quite a bit less, but they weren't interested.  Now just a year later, they are possibly interested in replacing the speaker system/DSP.  

The really funny thing is that within the last year, we have been called in to "fix" something like 6 systems (all rather expensive-some stupid expensive) that were not properly designed, and the proper system would have actually cost less than what they paid.  All of these systems were less than a year old!

[RogerOwens]

What are you looking for in a mixer? How many channels, auxes, groups do you need. I'll definitely throw in my vote for the Allen and Heath. I'm sure youve probably heard this but a lot of the mackie sr series don't seem to age very well. Thats not always the case but it might be good to factor in to your thoughts as most churches want their systems to last as long as humanly possible.
-Roger

[Winston Gamble]

Check out this sale for a slightly used GL board.
http://srforums.prosoundweb.com/index.php/m/99526/440/?SQ=ba 215fc6b7cee3a49bfe9c7a1825bd49

Winston

[ProSoundWeb Community]