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[Randy Jackson]

Here's the deal: I teach in a high school, and we are getting a new sound system installed, even as I am typing this. The line array speakers being installed are JBL Vertec sub-compacts. This is a 700 seat auditorium, and the line arrays were requested to be installed 5 feet from the outside wall, on each end of the stage which is about 40 feet across. They are currently installed about 12 feet from the outside wall because "you get less reflection off the wall this way" - the company installing wanted them even closer to center. I realize this is a vague description, so I guess what I'm asking for is a "rule of thumb." Should I make them move them out?

[Tim McCulloch]

Here's the deal: I teach in a high school, and we are getting a new sound system installed, even as I am typing this. The line array speakers being installed are JBL Vertec sub-compacts. This is a 700 seat auditorium, and the line arrays were requested to be installed 5 feet from the outside wall, on each end of the stage which is about 40 feet across. They are currently installed about 12 feet from the outside wall because "you get less reflection off the wall this way" - the company installing wanted them even closer to center. I realize this is a vague description, so I guess what I'm asking for is a "rule of thumb." Should I make them move them out?

No.  The installer is being your friend.  I've fought with a theater director for 10 years on this very issue.  He wants the arrays flown as close to the side walls of the auditorium as possible so as to "not intrude on the 'picture'."  This, after they put up show portals that turn a 60' proscenium into a 36' proscenium... and in the dark, at that.

The result is that 50% of the PA energy is hitting the side walls at an angle, creating a significant number of arrival times at any given seat and pretty much insuring that intelligibility is sacrificed upon the altar of "the picture."  And then they bitch when the audience can't understand the word play in Seussical the Musical.

Also, you need to go to your profile and change your "display" name to a real First & Last Name or the mods will be locking this thread.

Have fun, good luck.

Tim Mc

[g'bye, Dick Rees]

Here's the deal: I teach in a high school, and we are getting a new sound system installed, even as I am typing this. The line array speakers being installed are JBL Vertec sub-compacts. This is a 700 seat auditorium, and the line arrays were requested to be installed 5 feet from the outside wall, on each end of the stage which is about 40 feet across. They are currently installed about 12 feet from the outside wall because "you get less reflection off the wall this way" - the company installing wanted them even closer to center. I realize this is a vague description, so I guess what I'm asking for is a "rule of thumb." Should I make them move them out?

Listen to your installer.  He knows what he's doing.  And so does Tim.

[Bob Leonard]

Here's the deal: I teach in a high school, and we are getting a new sound system installed, even as I am typing this. The line array speakers being installed are JBL Vertec sub-compacts. This is a 700 seat auditorium, and the line arrays were requested to be installed 5 feet from the outside wall, on each end of the stage which is about 40 feet across. They are currently installed about 12 feet from the outside wall because "you get less reflection off the wall this way" - the company installing wanted them even closer to center. I realize this is a vague description, so I guess what I'm asking for is a "rule of thumb." Should I make them move them out?

Listen to your installer.  He knows what he's doing.  And so does Tim.

Ditto on the above.

[Randy Jackson]

So here are a few (crappy) pics of the install. This is just the stage-right array, and the large black square in the ceiling (upper right of the pic) is the center of the stage, as is the projector screen box you can see sticking down, and the can light between the two. Any thoughts on what you see in the pics? Would better pics help?

[Jordan Wolf]

It is quite apparent that you have a different opinion about the placement than they do - otherwise this thread would be over and done with.  If you came here expecting a response of, "Oh, that's all wrong - it should be done this way", I think you'll be disappointed.  What do you feel the installer is doing wrong, anyway?

Leave the installers to their work and try to enjoy the new system.

[Randy Jackson]

It is quite apparent that you still feel the installer is not installing the array clusters where you think they should go...so I ask: what measurements and models have you, personally, undertaken to back up this notion?

What do you feel they are doing wrong?

Great question!
In coming up with the design for this room, I consulted with a VERY experienced sound tech, who regularly mixes both nationally and internationally for well-known artists. His suggestion for placement was approx. 5 feet from the outside wall, even with the front of the stage.

The company doing the install has many installs for PA systems in gyms, football stadiums, etc, but only one other line-array theatre install that I am aware of, and it seems to me that they trust a computer software program more than experience. (Being in a school, they got the bid for the job.) Meaning no disrespect to the installer, but just want things done right, so I'm asking.

[RYAN LOUDMUSIC JENKINS]

In coming up with the design for this room, I consulted with a VERY experienced sound tech, who regularly mixes both nationally and internationally for well-known artists. His suggestion for placement was approx. 5 feet from the outside wall, even with the front of the stage.

Mixing both nationally and internationally for well known artists does not make one a great intasallation consultant or installer for that matter!

and it seems to me that they trust a computer software program more than experience. (Being in a school, they got the bid for the job.) Meaning no disrespect to the installer, but just want things done right, so I'm asking.

Maybe, just maybe thier experience as taught them over the years that by taking accurate measurements of the room, inputing the data into the SOFTWARE that is specifically designed for the application that they will end up with much better and way more consistant results than by listening to the guy that mixes nationally and internationally for well know artists on systems that have been deployed by other guys that know how to use the SOFTWARE to setup the systems correctly! 

And even better, they have learned with EXPERIENCE that the software will provide much better results than the guy the teaches drama at the school that knows nothing other than he/she wants the speakers in the corners along the walls because of the way they look.

[Randy Jackson]

Mixing both nationally and internationally for well known artists does not make one a great intasallation consultant or installer for that matter!

Maybe, just maybe thier experience as taught them over the years that by taking accurate measurements of the room, inputing the data into the SOFTWARE that is specifically designed for the application that they will end up with much better and way more consistant results than by listening to the guy that mixes nationally and internationally for well know artists on systems that have been deployed by other guys that know how to use the SOFTWARE to setup the systems correctly! 

And even better, they have learned with EXPERIENCE that the software will provide much better results than the guy the teaches drama at the school that knows nothing other than he/she wants the speakers in the corners along the walls because of the way they look.

Thank you for the sarcasm. I'm just trrying to make sure the $100k we are spending is being done right.

[Brad Weber]

Great question!
In coming up with the design for this room, I consulted with a VERY experienced sound tech, who regularly mixes both nationally and internationally for well-known artists. His suggestion for placement was approx. 5 feet from the outside wall, even with the front of the stage.

I think that Ryans' comments were not really intended as sarcasm, I believe they were intended to help.  So the person you consulted may be a great mixer, but how does that relate to their experience, knowledge, background, etc. in system design and installation and how they arrived at that recommendation?  Maybe they are highly qualified in systems design and installation and went to great lengths to determine the recommended locations but mixing and system design/installation are not the same thing and while the knowledge of either aspect is definitely a benefit in the other, experience and expertise at one aspect does not necessarily relate directly to the other.
 
While the pictures certainly help, it is difficult to offer many comments based on just the pictures and information provided.  We can't tell what the house is like or how the arrays relate to the audience, we don't even know if there is a balcony or anything like that.  We also don't know the intended use of the venue or system or what comprises the rest of the system.  The interaction with the acoustical environment and with one another and the resulting coverage, intelligbility, etc. are aspects that should have been considered during the speaker system design.

The company doing the install has many installs for PA systems in gyms, football stadiums, etc, but only one other line-array theatre install that I am aware of, and it seems to me that they trust a computer software program more than experience. (Being in a school, they got the bid for the job.) Meaning no disrespect to the installer, but just want things done right, so I'm asking.

Along the same lines, is the primary purpose of the venue to support national and internationally known touring artists?  If not, then might the other person's perspective also have limited relevance?  Was anybody involved in the system design other than yourself who has experience in the type of facility and uses actually relevant to your venue?  One thing that stands out is that I don't see a center array which while perhaps not common for touring sound systems is quite common in theatrical and auditorium applications.
 
Just out of curiosity, who designed the system and who requested that the arrays be installed 5' from the side walls?  Did the installer bid to design and build the system based on general input provided?  Did the installer bid to provide and install a system based on an equipment list that was provided to them?  Or did someone design the system, ideally using both modeling and experience for the speaker system, and create technical bid documents consisting of drawings and specifications that were put out to bid?  Was the location of the arrays defined to the bidders and they are now deviating from that?  I'm really just trying to understand the installer's role and how the arrays and the array locations were determined and defined.

[Tim McCulloch]

So here are a few (crappy) pics of the install. This is just the stage-right array, and the large black square in the ceiling (upper right of the pic) is the center of the stage, as is the projector screen box you can see sticking down, and the can light between the two. Any thoughts on what you see in the pics? Would better pics help?

I see the issue with where they hang... your auditorium has no distance between the proscenium and side walls.  Yes, this *does* intrude into the 'picture'.  In your case, I think the subs should have gone elsewhere, but that has implications for the array LF... but at least it would trim up another 5'.

The original architect did your school no favors when it came to retrofitting an audio system into his design 20 years later.

There are no clean or clear answers here, as Brad W. points out.

The rig will *probably* sound fine, but the design & install does present sight line issues.

Have fun, good luck.

Tim Mc

[Randy Jackson]

Brad & Tim,

Well, here's the deal. This school is in a VERY unpopulated area, and installers are not a dime-a-dozen out here. As I mentioned, I'm not sure my installer has much experience with this type of system. I'm not trying to undo everything they are doing, but, as I mentioned, I've been trying to make sure they don't have to redo stuff.

I was the one who researched and "designed" (I use that term very loosely) the new system, and I have learned a lot, but still know relatively nothing. I relied heavily on my friend, the "mixer-man" for his input. I know he has done installs as well, but is not as easily accessible to where I am.

The bid documents did specify 5' from the walls, even with the front of the stage, and the install company is insisting that 14' in from the side is where they should be for the best sound for the room. My other "informant" says 5' in, turned in 5-8 degrees.

I happened to walk through before anything was hung, and the installer told me "14 feet in, right?" I said, "No, 5 feet in." Then after I left, it was hung approx 12 feet in - not really a good compromise, if you ask me, and so here I am.

I'm not sure who to trust, so I'm asking questions here. Everybody pretty much says, "Trust your installer, they know what they're doing." If I had done that, I would probably have an EV system instead of a JBL system (crown XTI amps, DBC processor, Yamaha LS9-32, Sennheiser 835W mics).

I know that the truly "best" answer is, as you pretty much stated, "We don't have enough info to answer the question." I get that, but my question is more a generalization, and why would a man who installs and mixes specify 5' - also, many new performance hall installs I've seen around the area (500 mile radius, and not that many - rural area) have the line array speakers at the edge of the procinium, not half-way across it.

Yes, there is no "good" place to hang these things, and whatever we end up with, I KNOW will be better than before, but I want the "best" for the given situation. 

Thanks for your great responses, I really appreciate it.

Randy

[Brad Weber]

I know that the truly "best" answer is, as you pretty much stated, "We don't have enough info to answer the question." I get that, but my question is more a generalization, and why would a man who installs and mixes specify 5' - also, many new performance hall installs I've seen around the area (500 mile radius, and not that many - rural area) have the line array speakers at the edge of the procinium, not half-way across it.

Perhaps the missing piece is that the 'best' speaker location for any particular application can involve a number of factors.  That may include where they are relative to the proscenium opening but would typically also include factors such as the speaker pattern, the general system concept and the listener area to be covered.  What makes sense in one venue or application may make little sense in another.
 
Another potential factor, did anyone look in detail at the structure above the ceiling and how that might impact the installation?  It's not unusual when dealing with retrofits or renovations to have the existing structure and other building elements (ductwork, piping, consuit, etc.) impact where it is practical or cost effective to locate the speakers.
 
I am a bit surprised that arrays just 5' from the side walls would be toed in only 5 to 8 degrees, but then I don't know how the shape or size of the room, if the systems is intended to have each array cover part of the seating or to coiver all of the seating for stereo, etc.  Frankly, if the bid specs stated that the arrays should be 5' in from the wall and aimed in 5-8 degrees then that is what should have been provided unless a deviation was approved.  Were there any Shop Drawing submittals or a Change Order or anything like that where a different location may have been presented and approved in some manner?
 
However, I wonder if there could also be another factor involved.  Does it happen to be that the gear to be used and some aspects of the install were specified but the Installer is also responsible for providing a system that meets some specific criteria or performance?  If so, then if they believe that what was defined cannot provide the required results that puts them in a potentially untenable situation.  If you want the arrays 5' from the side wall then you might simply point out to the installer that the locations were specified and put in writing that they will not be held responsible for any resulting impact on the system performance.

We are greatly guessing here, there are so many variables that could be in play that we are limited to sort of throwing things up and seeing what sticks.

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