New Sound System: Advice/Recommendations/Rough Price Ranges

[nogh0st]

Hey CB folks. I run a small-medium sized auditorium for the college I work at. I need to start looking into replacing our almost 20 y/o sound system as I am starting to get distortion in the low end of some of our speakers. There are other factors involved, too. The speakers going just gives me a good place to start having conversations with my boss.

There are two main scenarios I am looking at. First is replacing what I've got with something similar: a standard stereo with center fill + sub PA system. The second is a surround sound system to make the auditorium more versatile. The student government advisor has displayed interest in getting the auditorium upgraded to do afternoon screenings for the students and he may be able to get our SGA to put some money into the necessary upgrades.

Here are some details about the auditorium as it is right now:

* Two Bose Panaray 502 A's for front left and right (suspended)
* One Bose Panaray 502 B for front sub (suspended next to front right; pointing into drop ceiling/catwalk :-/ )
* Three Bose Panaray 802 Series II's for rear left/center/right (suspended; wired in mono :-/ )
* One each Bose 802C-II and 502C system controller/processor
* Two Crown Macro-Tech 1200's and one Crown D-150A Series II power amps
* dbx iEQ-31 and I think a Peavey EQ of some kind for what I'm guessing room correction/tuning?
* Allen & Heath GL2800-32 FOH mixing console (fairly new, not looking to replace it)
* Fairly high drop ceiling (1.5-2 floors high at the tallest in FOH)
* Six sections of permanent seating: front left/center/right and rear left/center/right
* Seats about 800-850 with permanent seating; fairly evenly distributed among sections
* Can seat 1,001 with temporary seats
* Two temporary walls to convert the rear left and right sections to decent size class/lecture/meeting/presentation rooms
* No mounted/installed projector or projection booth setup; all ad hoc right now with projector set in orchestra pit as needed (looking into this as a separate project but may need to combine this and lighting into a total upgrade project)
* Auditorium is acoustically treated; have been told that the auditorium has great acoustics just needs a system to complement it

Any setup would have to have to be multipurpose and have excellent performance with live acoustic bands. We have a few major bluegrass/country events through the year and several dance recital/theater type events. We also have a middle school that does their choir productions in our auditorium.

Mainly looking for rough price ranges and downtime estimates. I'd install everything myself, but without any rigging experience the only thing I would feel comfortable doing would be the wiring and installation of the rack gear. The actual speakers I would prefer to be installed professionally so they are done safely and correctly.

I am going to have a professional come out and do a walk-through with me to get an idea of what it's going to take/what I need.

I can give more details or clarification if you need it.

Any help or advice you can provide would be greatly appreciated! :-)

[themuzicman]

Mainly looking for rough price ranges and downtime estimates.

You need to have a budget first. Once you have a budget, you can get gear accordingly which will determine downtime depending on how much/what type of gear is purchased.

I am starting to get distortion in the low end of some of our speakers

Have you considered that the distortion could be from the amplifiers/console/processing and not from the speaker cabinets themselves? I have a feeling when you say "some of our speakers" that the problem is pre-speaker as they wouldn't have an odd coloration all together. If you have any way to isolate gear, run a full range sweep signal from the amp to the speaker channel by channel. Gradually add in more gear until you get to the weak link in your chain. Finding what's adding in this coloration could save you some money. While you do have a Bose system (i'll try to not hate so hard :P ) you can still make the best of what you have by piecemeal upgrades to minimize you downtime.

[nogh0st]

@themuzicman: Coming up with a budget for this is a bit tricky. There is some money for the auditorium but it's not my budget and most purchases require approval from higher up. I have a rough idea how much is in it but not how much I would be allowed to spend. There are some other funding sources on campus, too, but they would probably require proposals. I talked with my boss today and we talked about a (very) rough $20-30k estimate for the project, but I don't have much to go on as far as figuring that out. We also talked about doing it in phases to spread the cost over a longer period of time.

[Koopdaddy]

I highly recommend bringing in a professional for this. They will be able to best help you figure out the best course of action for your budget.

[nogh0st]

@themuzicman: I did try to isolate some of the gear, EQ's specifically. I ran it with the bypass on and then physically bypassed the EQ. Didn't notice a change in the distortion. Do you have any recommendations for sourcing the sweep signal from a laptop (I have access to Mac or PC)? I don't have any tone generators/meters/etc. My console does have a (pink) noise generator built in. I have thought about upgrading the system in pieces but not sure on the best approach or a good approach, i.e., one speaker at a time, rack gear first, etc.

[nogh0st]

I highly recommend bringing in a professional for this. They will be able to best help you figure out the best course of action for your budget.

That's my plan. I'm just trying to go into it prepared. I guess my main thing is trying to figure out if we could afford a surround system or if it would be better to go with a traditional setup.

[FMEng]

A $30k budget seems OK for a basic system, but I doubt it would go far with a surround system, especially by the time it is installed. It's relatively easy to throw speakers into most places and make music sound nice, but it is another matter to design a system to acheive adequate speech intelligibility in large, live hall. This is why the professional is needed. So called good acoustics can mean great for music and a real challenge for speech amplification, or vise versa. There is seldom a middle ground in large auditoriums.

The Bose stuff is still current. Start by having them troubleshoot the system you have. It might be just fine with repairs by an expert. The distortion could be as simple as improper gain structure, a failing amp channel, or a damaged driver. If it can be repaired for small cost, then you can better evaluate whether it performs to your needs.

[MNicolai]

That's my plan. I'm just trying to go into it prepared. I guess my main thing is trying to figure out if we could afford a surround system or if it would be better to go with a traditional setup.

Surround sound only exists in your living room and movie theatres. In most auditoriums, you're lucky to get even stereo even if your rig is stereo or LCR.

The human perception of hearing a stereo source is dependent on the relationship between each individual audience member and multiple audio sources. If you have left and right loudspeakers, you have "stereo". I say "stereo", because really only the people sitting in the center of the auditorium hear two unique sound sources. Anyone sitting to the left or right sides will hear almost solely what is being produced from the loudspeakers on their side of the venue. Closer you get to the stage, the more "stereo" turns into left and/or right but hardly both.

If you're sitting in the back of the auditorium -- even if you're in the center of the back, you can forget about hearing two unique left and right sources. Most rooms will have enough reflections that by the time the sound hits you, you're hearing primarily a mono source.

For those people sitting in the center of the room, they may get a little benefit from hearing a true stereo source, but to the exclusion of the people at the far left and far right seating areas who are hearing a mix that is missing instruments and effects. Anyone sitting down center is probably only getting mono lip fills and anyone in the back is getting a mish/mash of "stereo" that's effectively mono.

Just to get a stereo system instead of "stereo" (let alone surround), you should be prepared on spending hundreds of thousands of dollars on a consultant or contractor to generate an EASE acoustical simulation model of your room, study your existing equipment and infrastructure, make your room as acoustically dry as a desert with acoustical treatments, and then install a sound reinforcement system that delivers a unique left and right channel to each member of the audience without the reflections that would make it harder to discern the difference between the left and right signals.

Surround sound in your living room is easy. It's a bunch of speakers pointed to a single common location that you can fit several people into if you're lucky, each mostly able to distinguish the different directions sounds are coming from. A movie theatre is harder because there is no single common location to point a bunch of speakers; the audience is spread out over a large area and one person's right channel is someone else's center channel. A live performance venue is worse yet because the loudspeakers are in addition to the stage volume, which will radiate out in every direction and from the stage without the defined directionality of a horn or a tweeter.

Don't get your hopes up for surround. You can't afford the reinforcement and acoustics necessary to make it viable, and if you could you'd probably still be mixing in left/center/right at best. I've seen one live show ever that was mixed in surround, and those were the sound effects for a production of The Comedy of Errors, which involved some 100 sound cues that were programmed and mixed on a Mac, then spit out in seven or eight channels into a digital mixer, which were then presented to the audience as stereo with a couple wedges in the upper balcony that made for interesting reverberated left and right fills.

The difference between stereo and "stereo" in this case is that the 1300-seat venue has a Renkus-Heinz IC Live system that Ralph Heinz personally came and worked on for the install. Each stick of ICL-R column speakers have arrays of 4 digitally-steerable high-frequency drivers that can be focused in on any area of seating on the main floor or in the balcony. There are 6 sticks at that venue, three on each side of the stage, so there are 12 digitally-steerable drivers for the left channel and 12 for the right. Add some lip fills and balcony delays, and you can discern left from right in almost any seat in the house. Not an inexpensive system, but it's crystal clear versus a conventional system.

[museav]

* Auditorium is acoustically treated; have been told that the auditorium has great acoustics just needs a system to complement it

What do you mean by "is acoustically treated"? And it has great acoustics for what uses? A concert hall and a cinema may both be acoustically treated and have good acoustics, but because they are intended for different uses they have very different treatments and acoustics. You mentioned acoustic and choral performances as well as movies, so you seem to be defining uses that would normally be associated with very different desired acoustic environments. Also, does the good acoustics include good sound isolation from adjacent spaces and quiet mechanical systems?

Pictures and drawings of the existing space and systems would really help, but a site survey is the only good way to approach something like this. How large is the space, is it shoebox or fan, deep and narrow or wide and shallow and so on will all be factors. So will knowing where speakers, the projector the screen, etc. can be located and how they could be mounted. Knowing where all the equipment is currently located and what options exist may also be relevant. FWIW, 1.5 to 2 stories would often equate to 15' to 20', which depending on the room shape could actually be a fairly low ceiling for a theatre or auditorium that seats up to 1000 people.

Also keep in mind that changes to the system, especially something like adding surround sound and a permanent projector, will likely relate to additional conduit, perhaps some additional power. That could have some cost associated with both design and installation. There will probably also be some cost associated with aspects such as tuning the audio system and any system design. And you might want to verify how much of the work you can or want do yourself both in terms of what is practical, how that affects aspects such as documentation, warranty and support, and whether any requirements related to a Electrical or Special Restricted SP-FA/LV (Special Purpose - Low Voltage) Contracting license might be applicable.

There could also be many details involved. For example, your GL2800 supports L/R + Mono but does not support LCR or 5.1 mixing so you'd have to work out how that would integrate into the system or look at getting a new mixer that does support surround mixing. Also, if you don't have drawings of the existing system then someone may have to spend significant time documenting what conduit, cabling, boxes, etc. do exist before they can start to look at what they can do with what is there.

Having to approach the work in phases due to budget is common but it usually makes sense to put together at least a conceptual overall design. There are several reasons for that. An rather obvious one is to be able to make sure what you do initially will integrate well into the long term plans. A less obvious aspect is getting all the infrastructure in place. If you have to add conduit and/or power for surround sound and a projector then it will probably relate to less down time and cost to do that all at once. I've seen venues do things like bring in scaffolding, etc/ to hang speakers only to then do it again a year later to run conduit and power for a projector when they could have saved themselves time and money by doing both at once.

As far as estimating costs or downtime, there are way too many unknowns. A $20k to $30k budget will likely not support everything you want, although it may be sufficient for a first phase of the work depending on what that is. Until aspects such as infrastructure, cable paths, available mounting options, the coverage required, the condition of the existing equipment and so on can be determined then there is no way to assess how far that budget could go or what might actually be required.

[nogh0st]

@MNicolai: I have been leaning away from the surround sound in my head because I couldn't visualize how it works. Our auditorium is very different from the theaters I have been to and I can't think of a good way for "everyone" in the audience to get good or true theater surround sound. I've been moving away from it in my head ever since our SGA advisor brought up the possibility. I can only think of a couple ways to do it but not correctly. We're getting a new building on campus with a multipurpose room that will have a home theater system, Blu-ray player and a 1080p projector (probably about the size of a 30-50 person classroom). It may not be as big as our SGA advisor was looking for but it will be better suited for a theater "experience".

[nogh0st]

What do you mean by "is acoustically treated"? And it has great acoustics for what uses?

I don't have access to the original design documents as far as I know (or the designer), so all I can say is it seems to have been designed with live performances like dramas/plays and acoustic bands (esp. bluegrass and country). Maybe "acoustically treated" isn't quite the right term (I'm a couple years into the industry). There is sound absorbing tile along all the walls up to the ceiling.

FWIW, 1.5 to 2 stories would often equate to 15' to 20', which depending on the room shape could actually be a fairly low ceiling for a theatre or auditorium that seats up to 1000 people.

That's my brain's fault. To me, it's a fairly high ceiling, probably something closer to like 50' but I'm terrible at guesstimating length/distance. The control room in the back is up one floor above the entrance and the ceiling in the house is about one floor above that--threeish floors in total. The seating/floor is on a gradual down grade (can't remember the technical term for that style of seating).

For example, your GL2800 supports L/R + Mono but does not support LCR or 5.1 mixing

I forgot that the Mono on our board doesn't work as a center channel.... I really wouldn't be interested in mixing live events in surround, just running the output of a DVD through a surround processor. But like I said above, I'm leaning away from a surround system just for the impracticality and most likely very high cost of it.

As far as estimating costs or downtime, there are way too many unknowns.

I'm just looking for some ballpark figures so when we have "the talk" I won't be going in throwing out huge numbers without any basis. I am going to attempt to identify bad components in the system to see if I can get some more life out of it before we go spending thousands of dollars on something we could fix with just a few hundred....

Thanks to everyone who has posted so far! I feel much more informed and have a clearer idea on what direction we should probably go.

[Aman121]

Just curious, before the speakers started failing, was the system aquedate for your needs or did you notice shortcomings? If what's in there was ok before the problems, why not just replace the failing driver or get the amps serviced and save your upgrade tokens for lighting or something else? I'm a fan of repair vs replacement, as long as the equipment didn't have shortcomings before.

[museav]

Just curious, before the speakers started failing, was the system aquedate for your needs or did you notice shortcomings? If what's in there was ok before the problems, why not just replace the failing driver or get the amps serviced and save your upgrade tokens for lighting or something else? I'm a fan of repair vs replacement, as long as the equipment didn't have shortcomings before.

Very good point. The fact that you apparently aren't sure of the purpose of the equalizers may also indicate that their and perhaps other device settings may have been altered over the years, thus there could potentially be significant value in having someone come in and go through the system gain structure, perform a system tuning, etc. That party may verify that there is a hardware problem or they may be able to get acceptable performance out of the existing system. And after that exercise they will probably be in a much better position to offer recommendations for what system revisions or upgrades may be appropriate in order to meet your current and known future goals.

I am always wary of offering system cost estimates because there are so many aspects that could be missed or misinterpreted. For example needing to revise or add conduit or power could add hundreds or thousands of dollars of cost. Or a specific example, I had a project where I had put together a speaker concept and had a Structural Engineer perform a cursory review regarding flying what I ceonceived but once the Contractor worked out all the array details for what they were providing and had a Structural Engineer looked at that and the existing structure in greater detail that resulted in a $20k+ additional cost for the additional substructure and scaffolding that turned out to be required. On that project the scope was large enough and we were lucky enough to be sufficiently under budget elsewhere to absorb that cost but with a smaller budget such costs could be disastrous and are imp[ossible to address via a forum.