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Theater Install - Subwoofer Possibilites?

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Cody Hazelwood:
Before I get into this, I want to give you a little background on myself.  I'm 21 and I've been doing freelance live sound since I was 16.  Lately, I've been getting into system installs, and I've worked with several churches, correcting wiring issues in their installs and retuning systems.  So far this is the most complicated system design I've gotten in to, and I want to do it right.  I want to make this a career, and I figure just doing it is the best way to get in to the business.  (I'm currently enrolled in college as a Professional Computer Science major, Recording Industry minor, and Electro-Acoustics minor)

I'm installing a Mono system (but would like to run conduit to support a LCR system in the future).  The system will be used primarily for dance, clogging, theater performances, etc, but it needs to be able to support anything, including rock bands.

The main issue I'm having is subwoofer deployment.  The room has an atrocious balcony (about 1/3 of the seating and low ceilings).  Using delayed speaker clusters makes coverage not so difficult for the tops, but because of the omnidirectional nature of subs, and reaction with the walls, I'm sort of lost on where to go design wise.  I've been experimenting with MAPP, but I don't think it accounts for ceiling and floor.  I definitely want to make sure that the LF stays as far away from the stage as possible.

Would it be a bad idea to use a cardiod type setup for the main floor, and a delayed cardiod cluster for the balcony?  I prefer to hang the subwoofers so the coverage is more even among the seats.  If that was an option, would I need to make a vertical array to steer the beam down to the seats?

Thanks for any advice.

Here's some of the plans for the room:

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The chandeliers are in two rows about 13 feet off center.  The 2nd lighting bar is about 3 feet closer to the balcony than my first drawn balcony speaker.  I don't know it's elevation yet (plans for everything are still preliminary).

Ivan Beaver:
The idea of a cardoid setup for the balcony is one that "could" work.  But if you look at distances from a center flown cluster to the seating areas-there is not much variance-so not a lot of difference in SPL.

Yes the very back up the upper balcony is further away-but the area is a good bit "smaller", so it is a different acoustical environment-and you may get some room gain in those seats.

It would be nice to also know what the budget (for the subs) is (including amplification and whether or not labor needs to be part of that).

Also what the main loudspeaker is-to make sure the sub system could keep up with it.

I try to stay away from "complicated" sub setups, because there can be all sorts of "unknowns" that can creep up-due to room modes and such.

Untill we get accurate 3D modeling of sub freq, it is going to be hard to figure how everything will interact.  So my feeling is it is best to stick with simplier setups.

A while back I did a kinda complicated setup with various cardoid sub setups and a quad directional setup.

When I put my mics all around the results were not what I expected.  Better than if I had not done it-but not as good as I would have liked.

Of course the whole idea was to keep the energy off of the stage.  BUt all that did was get the musicians upset because they felt the system did not have enough low end-because they could not "feel" it on the stage.

So what is good, can be bad at the same time-for exactly the same reason

Cody Hazelwood:
There isn't a specific budget.  The project is being funded by government grants and a large donation from an organization in town.  I was asked to design a sound system that would do the stuff that they need it to (mostly theater shows, concerts, clogging, etc.) with room for expansion.  They have quite a bit of money, but if money runs out, they want to cut components to save for later, not quality of the components used.  They expect to see prices like $20k for an iLive, etc.  But at the same time, money isn't unlimited.  I'm trying to keep all speakers/amps under $15k, excluding monitors.

Labor is going to be mostly donated (this is a pretty big deal for the community, so everybody's willing to help).  The electrical contractor is running all of the conduit that I specify.  The general contractor will hang the speakers once I specify where they'll go and where they'll be aimed.  I will lead the laborers in running wire, etc, and I will make the connections myself.

For amplification, I was planning on using QSC PLX2 series amps (only models ending with a 2).

I haven't picked specific speakers for the balcony yet.  I'm still trying to figure out where they're planning on putting the light bars.  For the main floor, I was thinking about the EAW MK5396 (90x60, 15") for the main center speaker and the EAW MK8126 (120x60, 8") as the downfill for the front rows.  I open to suggested changes on those if there is something better at a comparable price.

Brad Weber:
Cody Hazelwood wrote on Sat, 08 January 2011 22:56
Labor is going to be mostly donated (this is a pretty big deal for the community, so everybody's willing to help).  The electrical contractor is running all of the conduit that I specify.  The general contractor will hang the speakers once I specify where they'll go and where they'll be aimed.  I will lead the laborers in running wire, etc, and I will make the connections myself.

Does the General Contractor have experience doing this?  Do they have any certified riggers?  Is a Structural Engineer reviewing the connections to structure?

On the Balcony floor plan, is that a wall dividing the upper Balcony in half?  It looks to have a door in it, indicating it may indeed be a wall.  That would probably affect what you do to cover that and make the concept of a future LCR system difficult for that seating.

A system that is being built on financial and labor donations and that is using EAW MK speakers is usually going to have difficulty justifying the cost associated with multiple directional subwoofer arrays.  You might also want to look at whether the coverage of the main subwoofer array is likely to also result in coverage well into the balcony.

This also brings up that looking at your section I noted what appears to be a lot of overlap in coverage.  What looks like a flown front fill overlaps significantly with the main while the main and front balcony fill also overlaps significantly.  Also remember that the pattern of the speakers is not the same for all frequencies and that the speakers will be less directional at some frequencies.

On the front fill, on addition to the overlap in coverage wit the main and pattern issues noted, you might also have issues in terms of imaging.  The fills are probably most relevant to speech intelligibility but the location of the front fill could also result in the perceived localization of the image being pulled up rather than being from the source on stage. This is more critical in lecture and theatre type applications but if you incorporate front fills you might want to consider incorporating them in the front edge of the stage.

You haven't seemed to mention anything about acoustics, is anyone addressing the acoustics of the space and are you coordinating with them?

Planning for a potential future LCR system means more than just some additional conduit.  It should include things like planning for hang points, being part of the coordination with acoustics, being included in the power and rack space provisions and perhaps even being accounted for in the system processing used.

Speaking of which, do you have a system processor in mind?  With the multiple delays, thoughts of subwoofer arrays and potential of an LCR system, that could require a fairly large and powerful system processor.  That could be a factor if that is to be part of your $15,000 budget.

I'll just offer my $0.02 from experience.  Projects with no specific budget that depend on grants and donations tend to end up with grand goals and much less grand realities.  There are certainly exceptions but with no budget identified, something I would suggest should be done and committed to as soon as possible, then it is very likely that you will be asked to cut back from whatever you initially propose.  If that happens, then aspects such as conduit, floor boxes, power and equipment space are much easier and less expensive to deal with during construction and are often a place where it makes little sense to not make cuts upfront.  Speaker systems are often another area where it makes little sense to make too many compromises as once they go in they are unlikely to be changed unless there are other major changes.  While the iLive, and I assume you mean the iLive-T, may be a very good option, I have to say that with a $15,000 budget for the entire speaker system, a $20,000+ mixing console seems a bit out of balance and if budget cuts have to be made the console, along with some ancillary items, may be the first place to look for reductions.

Cody Hazelwood:
I'm not sure about the General Contractor's experience with hanging speakers.  The project has structural engineers involved, and in the material that I submit, I'm going to note that they will be required to develop the hanging methods for the speakers.  I'll provide the speaker manufacturer's designated flyware.

The balcony wall is about 3 ft tall.

As far as the speaker placement, isn't it normal practice to aim the center-line of the speaker at the back seat that you are trying to cover?  I was worried the front fill might cause an issue, but there's almost no way to aim the center line of a speaker at the back seat on the main floor and not have some over lap in the balcony.  My reason for starting with the center only system is to ensure clarity, and this will have a lot of lecture/theater type stuff going on.  The front of the stage is removable, so I can't put speakers or inputs there.  I considered line-array, but I don't think I could fit a long enough array in the center without blocking the view of the stage some, and I'm not sure that it would be necessary.

As far as acoustics goes, there is no acoustical engineer in the project.  Every time I mention acoustics, people say that they're great. :/  But, I am supposed to be meeting with the architect soon, and I'm going to insist on diffusion at least on the front wall of the balcony and the front wall of the projection room to limit some reflections.  While the RT60 is the room is suprisingly low for the size (even without seats or carpet), I'm slightly worried about reflections once the speakers are hung. I don't really know enough about acoustics to draw out exact acoustical plans, and this is a renovation/restoration project, so they are trying to restore the old look.

I've left rack spaces in the plans and I/O on the system processor for the LCR system.  The processor I'm using is the Yamaha DME24n with the MY8-ADDA expansion card.  This gives me 16 in / 16 out, and the processor is incredibly flexible.  I've installed one in a church and it made an unbelievable difference in their system.

If I need more than $15k to do the center right, then that's what I'll tell them.  I'm trying to set the budget overly high (like including the whole LCR system up front) and when they tell me to cut the budget, I'll drop the the LR and try again.


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