What mains do you use?

ACTSTech

Well-Known Member
We're moving forward with our reno project and it's time to address the house mains, or lack thereof. I have a pretty good idea what I'd like, but I wanted to see what people are using or in some cases, still not using. I've heard some horror stories about what to stay away from. Any thoughts?

In our case, the hall is going to be about 80' long and 40' wide, speakers will have to be surface mounted above the proscenium 21' off the floor (18' off the deck) and about 10' from the first row. I'm hoping to buy 4 of the QSC K8.2 powered speakers to mount on the proscenium which I think would be more than enough for our shows. I'd like a mini line array but that's not going to happen. I'm not 100% sold on the QSCs but I've heard them and I think I'd be comfortable. My only concern is that they're powered, so if something goes, it's the whole unit, not just a speaker or an amp, but it's the way things are done now.

Before I order, is there anything anyone's fallen in love with that they want to share? Talk me out of my insanity?
 
My immediate thought - don't spend any money on a loudspeaker system until you can get an in person review and walk-thru of the auditorium with a person who does audio for a living.
 
My immediate thought - don't spend any money on a loudspeaker system until you can get an in person review and walk-thru of the auditorium with a person who does audio for a living.

^^This.

Different systems for different applications, and it’s pretty rare that the best course of action is simply hanging new speakers.

Also, brand loyalty has its benefits in terms of ensuring you don’t left up a creek, but it’s not a good way to select speakers. Nor are line arrays usually a good choice. Line arrays simply for the reason of wanting line arrays may make your sound system *look* louder, but that doesn’t mean your system will actually sound any better. In the wrong application — which is what many line arrays get used in — it often actually makes your system sound worse.

In a vacuum, the QSC K.2 speakers are a great product, but I would almost never recommend them as an installation speaker in a large performance space. Generally if I’m spec’ing them for something, it’s a dance studio or a rehearsal room, and I tend to stay away from the 8’s because they have too wide of a pattern and don’t reach as low — especially if you don’t have subs to fill out the LF with. ——— But again, that’s in a vacuum without any specific consideration for a particular room and is not any value statement on whether they would or would not be suitable for whatever your particular use case is.
 
Echoing (haha) the above, get a pro in your space. Lighting you can fudge a little, but acoustics are much less forgiving. You need to find good products that people understand the quirks. If no one really knows the response curve, you'll end up with acoustic mush.
 
I'll go out on a limb and say that four point-source speakers (particularly ones without great pattern control, like the K8.2s) in what sounds like a pseudo-array are almost certainly not what you really want. They're decent enough speakers where appropriate to the situation; but this very likely isn't one of them. Rather, it sounds like a recipe for all sorts of comb filtering and muddiness.

I also suggest what others have said: get someone who is truly competent to do this sort of work to help you spec out your speaker(s). There are a myriad of details that should be considered, beyond simply the length and width of the house: how live it is, how high the ceiling is, how the seating is laid out, what sorts of productions you'll be doing (lectures and rock concerts have very different requirements!), the budget, and so on. A knowledgeable professional will understand them well. At best, I could only make a rather hazy guess myself. (There may also be some acoustic treatments for the room that would make a world of difference.)
 
Echoing (haha) the above, get a pro in your space. Lighting you can fudge a little, but acoustics are much less forgiving. You need to find good products that people understand the quirks. If no one really knows the response curve, you'll end up with acoustic mush.

There's also a dirty little trick that with decent control from a DSP, you can often extend the mileage out of an existing system of less-than-good products if it's at least time aligned and tuned correctly. Earlier in the pandemic I helped a local theater here that had a VRX center cluster, some EAW corner fills, and a weird assortment of JBL Control speakers -- none of which were particularly great choices for that shoebox of a room. In about 15 minutes in the room I determined the VRX crossovers were toast. Probably had been that way for years -- but their resident audio tech hadn't really done any critical listening to the system to realize that the VRX speakers were hardly putting out sound when they should've been able to peel the paint off the walls.

The theater replaced those crossovers, slid some speakers around, and hung some curtains near their corner fills where they had lots of comb filtering from their corner fills that were interacting with the side walls they were near. I brought my personal DSP and Smaart rig in, we tuned and time aligned every amp channel independently, established the proper gain structure, and then transposed those settings into their the output processing for their mix console. Complete night and day difference spending only about $400 in parts and largely reusing what they already had on-hand.

It's not often you get that lucky, but it is pretty common that venues aren't even in the ballpark of being tuned correctly and are getting only maybe 30-50% of the performance out of their existing system as they could be getting if it was optimized with minor adjustments. Even a large number of professional integrators don't tune with Smaart or anything like it. Not uncommon they tune with an RTA or sometimes just an app on their phone, or by earballing to a favorite music track they like -- which tuning to a specific music track is a terrible idea because people tend to try to remaster the track to how they like it sounding and not how it was originally produced.

All of which is to reiterate that speakers are only one piece of a larger jigsaw puzzle for having a coherent, balanced, and flat sound reinforcement system.
 
Thanks for the help and suggestions. I have to chuckle at what most of you have said, and I fully agree. To be honest, I often print these discussions to take to the board so that people see that there's experts who share my opinions. Then they most often do whatever they want anyhow, but at least I can say I, and many others, told you so after they're proven wrong.

I'm not sold on the QSC's in all honesty. The reason I chose them was more budget over anything else as well as looking at who the end users will be. The design team for the renovation have already changed designs after the final plans were drawn so I don't feel comfortable saying what the venue will be. Nor do I feel comfortable paying an acoustic engineer to come in now, before anything has started, at $3000-$5000 to tell me what they think the venue will need when the plans are going to change. Not against paying (I posted this earlier), but not now.

In terms of getting someone to consult... I contacted five vendors I have worked with in the past and three additional vendors that the electrical engineer who did the drawings recommended. The ones I have worked with all said it's too early to come in, which I understood. The three that came recommended... well none of them want to deal with a small venue. One said if I wasn't looking at Martin or Meyer rigs it wasn't worth his time. Another said not interested, and the third that actually came brought Bose room speakers to demonstrate. Two vendors contacted me after seeing RFQs, and neither really seemed interested. One insisted that Danley was the only way to go in a "small venue" and the other had some "spare" Renkus Heinz IC2-FRs that he thought would integrate with some EVs he had left over from a high school install. After he heard my take on the install, basically what was in the plans and specs which he obviously never read, he thought maybe we'd need more...

I wasn't really fishing here, but I was just curious what others thought. @DrewE , you made a good point about the size of the room. The reason I can't commit to what the room will look like is because the room keeps changing. The architect insists that we need plywood clouds to help with the sound, but he can't explain why he has them where he has them other than "this is what I typically draw up". The walls were originally wood, then became rockwool behind drywall, then became drywall with fiberglass acoustic panels that were more for aesthetics than noise, then a mix of the above. Nothing that he's drawn is acoustically-minded, it's aesthetically-minded.

The underlying problem is that we won't know what the room is until it's done. Then we can proceed. However, if we need a budget to apply for loans and grants, and it's not in line with what's out there available for grants and loans, we're going to be stuck. That's why I'm trying to cobble together my own specs and get some opinions. I'll HAPPILY turn everything over to the pros when it's time to do the install, but if I don't have a budget for them to work with, it's going to be tough.

Again, I appreciate all the input and I am making notes on my drawing as I go, so please don't hold back in roasting me. I can take it.
 
Not uncommon they tune with an RTA or sometimes just an app on their phone, or by earballing to a favorite music track they like -- which tuning to a specific music track is a terrible idea because people tend to try to remaster the track to how they like it sounding and not how it was originally produced.
Guilty, sort of...

When I first got involved with this group, they were having MAJOR problems with their sound system, specifically the wireless body packs and terrible feedback all around. First thing I did was played my favorite track from a recording (CD, Uncompressed, not mp3) and heard how it sounded. Their sound guy wanted to know what he needed to change in the EQ, which was how they addressed all their issues. After resetting the board back to factory state and getting rid of all the mistakes they'd piled on top of mistakes, it still sounded bad. Went to the amp, undid the DSP settings the installer applied, retuned the room correctly, there was a world of difference. Not amazing, but incredibly better. Yes, their sound guy made mistakes, but the professional installer set them up for failure. He apparently slapped some pre-set notion of what the room should sound like on the amp and really hurt them. But when he played music for them, he showed them how to use the EQ, make the smiley face with the sliders, and took their money. You make a good point. Earball after you do the hard work, and go by the mastered version, not your car stereo.

I'm putting this in the report to the board, thanks!
 
Guilty, sort of...

When I first got involved with this group, they were having MAJOR problems with their sound system, specifically the wireless body packs and terrible feedback all around. First thing I did was played my favorite track from a recording (CD, Uncompressed, not mp3) and heard how it sounded. Their sound guy wanted to know what he needed to change in the EQ, which was how they addressed all their issues. After resetting the board back to factory state and getting rid of all the mistakes they'd piled on top of mistakes, it still sounded bad. Went to the amp, undid the DSP settings the installer applied, retuned the room correctly, there was a world of difference. Not amazing, but incredibly better. Yes, their sound guy made mistakes, but the professional installer set them up for failure. He apparently slapped some pre-set notion of what the room should sound like on the amp and really hurt them. But when he played music for them, he showed them how to use the EQ, make the smiley face with the sliders, and took their money. You make a good point. Earball after you do the hard work, and go by the mastered version, not your car stereo.

I'm putting this in the report to the board, thanks!

I've seen the "generic DSP" settings applied in too many installations, but the one that took the prize was the auditorium that had multiple DSP devices installed in the amp racks, but only 2 of them had audio routed through them... and the processing was only bare-minimum crossover settings. I spent a couple of hours and used 2 XLR cables from their inventory to make audible improvements to their rig. I'd been brought in because they'd had a lightning strike that gave their DSP some kind of electronic amnesia... ironically one of the unused (but the pilot light was on!) units retained its settings so I manually transferred them and proceeded with my system tuning.

They had a number of system design problems that could not be addressed for reasons of physics and venue internal politics, so I did the best I could and left them with a working rig that sounded better than I'd found it. Sometimes the 'wins' are incremental.
 
Here's a quick story for the board. A mentor of mine was on a committee that was overseeing the design of a college auditorium/gymnasium of around 3000 seats, the largest in the area at the time. Nearing the construction phase, they were going through the cost cutting exercise. The sound system became a potential target for cost cutting.

My friend sat quietly and listened as the committee started taking the hatchet to the sound budget, when they realized their resident sound expert hadn't said anything. So they asked him for his opinion, which he returned with a question. The question was, "is there budget for more restrooms?" (Restrooms being one of the more expensive things to construct, due to plumbing and ventilation.)

Naturally, the answer was no, just enough toilets to meet code. The committee grew curious as to why he asked the question. He went on to explain that when people can't adequately hear the entertainment they get bored. When they get bored, their mind wanders and they focus on themselves. When they focus on themselves, they'll notice the need to pee, and the restrooms will be used heavily, requiring more of them. He got his sound budget.

Why build an auditorium at all if the acoustics and sound system are going to be last minute and done on the cheap?
 
Why build an auditorium at all if the acoustics and sound system are going to be last minute and done on the cheap?
Agree and disagree.

This group is amateur, but after 10 years of not losing money on any of their shows, they got, perhaps unfairly, targeted by local governments and lost their performance venue. I'll spare details, but the choice was to either fold or try to find a new home. They're attempting the latter. I applaud their tenacity and drive. I get frustrated by their short-sightedness, but I work because I enjoy the work.

Also, this isn't going to be a world class venue. This will never compete and bring in touring shows or big names. The house system would never work for those anyhow, it would be rented in for anything to bring it to spec. They need something that will work. And unfortunately, the "experts" in the area see dollar signs, not functionality. It's like the power windows in the rear seats of your car when you're the only person who will ever ride in the car. Sure, it's a nice option, but why should I pay for something I'll never use. Do I really need heated rear seats as well? It's sort of value engineering at this point. I know I'll get blasted again for saying that, but for amateurs, you don't need A1 quality. The sad fact is that poor quality is ACCEPTED here. A high school streamed their musical last month and only half of the wireless mics came through, no one seemed to care. Everything gets a standing ovation. All I'm trying to do is get to far above average for now, and I know it's less than idea, but if it's between being above average or out of business, I'll choose the former.
 
On a point of order, amateurs aspire to achieve A1 quality but accept the reality of finite resources. Performance art does not require premium theatre technology. It requires people willing to share themselves with an audience. Anything extra is a bonus.
Amateurs perform for the love of performing. If they had no option, they'd find a barn or grange hall or someplace. We're trying to get them into a building that's not ideal nor probably ever will be, not because they want a state of the art venue, but because they want a home.
 
Amateurs perform for the love of performing. If they had no option, they'd find a barn or grange hall or someplace. We're trying to get them into a building that's not ideal nor probably ever will be, not because they want a state of the art venue, but because they want a home.

As was stated when our home was (temporarily) lost to a flood: "[We are] more than just a building, we're a community." We played in high schools, one memorable middle school, and finally a movie threatre-cum-Staples that was abandoned. We built a theatre from a concrete slab inside a building. And our office ran out of a former funeral home...
 
I just had a long conversation with a gentlemen who asked to not be named on here, but was very helpful, and I thank him. I appreciate the help and input, and more than anything, the therapy of actually venting and vocalizing my thoughts.

We played in high schools, one memorable middle school, and finally a movie threatre-cum-Staples that was abandoned.
As stated, the group TRIED to rent several high schools who refused, mostly because their either don't want outside groups or the stage is the only rehearsal space for their groups so nothing on the stage can be permanent or left there (one recently lost their band rehearsal room to become a wrestling practice room). Most churches won't allow groups any longer because they run too many services and don't want things longer term. They ended up renting a small venue that had three weekends open (then tried to take back the middle weekend so they could have a Red-Hat Ladies meeting Friday and a baby shower Saturday) but Covid shut them down after weekend one. If this building gets done, it will serve a need for not just one group.

Again, I'm not trying to go in the cheapest route, just the most feasible at the moment.
 
Since there's been tons of discussion about the right way to do things, which should be followed, acoustician, engineering etc.,
I think you're doing the right thing here - ask questions of the architect on things that will possibly create a worse listening environment. In general, very general, large swaths of reflective material like wood, shouldn't be installed in venues that are going to be highly amplified. They should be installed in highly acoustic environments like those used for a symphony.

In general, again very generally, the more you plan on amplifying, the more diffusion and absorption you should have especially in the areas you can envision the speaker audio hitting soonest. This is why padded seats are nice.

What I would recommend for your lower budget, somewhat DIY install is a speaker that has a rotatable horn. This will, at the least, save you from wherever your engineer decides your mounting point is, only to realize it's 3' from a wall. In typical DIY fashion, the installer would point the speaker away from this reflective surface, only to point it directly at the stage, forever causing feedback for anyone close to the lip. At least if you spec'd 3-4 cabinets with rotatable horns you can decide, once the building is built, that LCR makes more sense than LR since you're going to have only 50degrees of width on the sides and need to make up for that with a center channel.

my 2c
 
Time for a book plug...

Welll, it seems if I put the Amazon URL in, the forum software converts it to a media tag with no URL.

F. Alton Everest/Ken Pohlmann "Master Handbook of Acoustics, Sixth Ed" McGraw-Hill

Mastery of each page is not required, but grokking a concept is easier when one understands the scope.

In this case the room is the biggest factor in the results and whatever loudspeaker wizardry might be needed, cannot be determined until the architect has done his/her/their damage.
 
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In general, very general, large swaths of reflective material like wood, shouldn't be installed in venues that are going to be highly amplified. They should be installed in highly acoustic environments like those used for a symphony.
Since this was an old church, the walls are wood panels over plaster. Highly reflective. Adding more clouds over the area where the pit orchestra might sit sounds like a recipe for disaster. Especially since when I ask how the panels are constructed and aimed, I'm told they're "a beautiful golden wood" but the positioning is more aesthetic than functional. Also, they're not movable once they're up, so if they're reflecting in the wrong direction, too bad.

In general, again very generally, the more you plan on amplifying, the more diffusion and absorption you should have especially in the areas you can envision the speaker audio hitting soonest. This is why padded seats are nice.

I set up the speakers that the group has just to demonstrate some of the issues. I explained that even though the room isn't constructed, that they could hear some of the problems that already exist. After playing a few things, they asked if maybe I could just turn up the volume... And I did... And then the lightbulbs went on. They finally got that louder does not equal better. More speakers also will not equal better. So they're getting it. Then they started asking questions, like why do they hear "that weird echo" behind them. When I explained that the front of the balcony is a great flat surface to slap the sound off of, they understood why we need some treatment of some sort.

What I would recommend for your lower budget, somewhat DIY install is a speaker that has a rotatable horn.

How about the "professional installation company" that told me they have a 120 x 60 degree coverage pattern speaker that would be great mounted "anywhere"

I appreciate and agree with you 100% Thank you for the recommendations as well.
 
I'm also feeling that there's probably a good amount of politics going on with the decision making by management.
Since you did a demo with what I'm assuming are the QSCs on sticks, would they be open to hearing other demos by local distributors?

Also, how are you going to try and convince them of improved acoustics? Maybe you could rent a couple legs and hang them at 45s in the back of the room so they can hear what it's like to add some absorption?
 

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