There is a long story here which you can skip, but I am the TD for a non-profit theater. The space is a black box with modular seating and ultimately flexible design. My current audio is 4 Yamaha 12" and an old Peavey M7000 amp. Remember those big brown anchors? The array is a cluster in the middle of the room hanging on swivels so I can point them wherever the audience is. Two of the speakers have blown horns and one has a 12" driver that was replaced with a paper cone/paper surround thing that looks like it came out of a Magnavox Phono from 1973. The phasing as you walk around the room causes dizziness for anyone with a good ear.
The theater obviously operates on a tiny budget. I was quoted $28k for a new audio setup that would be great, but that's more grant money than we can solicit in 5 years. So I thought, "hey, I've built dozens of speakers from someone else's plans, I should learn how to design one myself."
So here I am. I have a small truckload of MDF and particle board, a soldering iron, and $2500 in the budget. I'm hoping to whip up 6-8 small active wedges (think kind of like some full range center-fills) that I can hang from the grid over the audience pointing down a bit. Kind of like speakers in a car headrest instead of in the doors. For each show configuration, I can hang and point them, then send to a digital snake and XLR to each one. Low frequencies can be handled by a Yorkville sub someone donated.
Something that I can build with Dayton drivers for fifty bucks, slap on a $35 plate amp, and make it happen... instead of $750 each like these passive VTC Inceptions
TL;DR.... Looking for some plans for a 5.25-6.5" bookshelf-sized speakers on steroids that I can slap a plate amp on and use as a PA in my theater until the grant fairy leaves me a big check.
The space in question: (wide angle shot) 50 x 60 black box.
The theater obviously operates on a tiny budget. I was quoted $28k for a new audio setup that would be great, but that's more grant money than we can solicit in 5 years. So I thought, "hey, I've built dozens of speakers from someone else's plans, I should learn how to design one myself."
So here I am. I have a small truckload of MDF and particle board, a soldering iron, and $2500 in the budget. I'm hoping to whip up 6-8 small active wedges (think kind of like some full range center-fills) that I can hang from the grid over the audience pointing down a bit. Kind of like speakers in a car headrest instead of in the doors. For each show configuration, I can hang and point them, then send to a digital snake and XLR to each one. Low frequencies can be handled by a Yorkville sub someone donated.
Something that I can build with Dayton drivers for fifty bucks, slap on a $35 plate amp, and make it happen... instead of $750 each like these passive VTC Inceptions
TL;DR.... Looking for some plans for a 5.25-6.5" bookshelf-sized speakers on steroids that I can slap a plate amp on and use as a PA in my theater until the grant fairy leaves me a big check.
The space in question: (wide angle shot) 50 x 60 black box.
This is very very important: do not hang anything over anyone, without proper certified rigging, installed by someone qualified.
Commercial loudspeakers intended for hanging are tested to destruction to ensure the cabinet can be supported from the intended rigging points, and to ensure they can hold up other speakers when used as part of an array. This testing is closely documented, such that insurance companies etc would be happy to sign off on it. When it comes to heavy things falling on people, you're talking many millions of dollars in personal damages - those insurance companies don't take that lightly.
Chris
Commercial loudspeakers intended for hanging are tested to destruction to ensure the cabinet can be supported from the intended rigging points, and to ensure they can hold up other speakers when used as part of an array. This testing is closely documented, such that insurance companies etc would be happy to sign off on it. When it comes to heavy things falling on people, you're talking many millions of dollars in personal damages - those insurance companies don't take that lightly.
Chris
I built a pair of BFM SLA Pros with PE 295-015 drivers. They are the 2X6" version and driven with a battery powered 2X50W amp, they fill my yard nicely. It looks like you will just be doing voice and maybe a little music at something less than rock concert levels, so these should be fine on a couple of stands. Let me know if you can't find the info you need and I'll send some links or more details. The plans were $15 and worth every penny.
Very wise advice, and I always take safety and liability to heart. I'm that guy. I'm the rigging dude. Educated, qualified, and (although currently expired) certified. Anything like that I build gets fully encased in epoxy and fiberglass resin in a vacuum bag with rated t-nuts and I would actually use some leftover yokes and clamps I have from my pile of dead lights.
Gordon, I'll look those up, thank you. If I can't find anything I'll give a shout.
As you can see from the photos, the furthest a speaker would have to be from anyone's ear is about 15 feet, so you're correct that they don't need 300w or rock concert levels. In fact, I rarely use amplification on actors. Maybe 4-5 times a season. Most plays done here are either 1/4-P, vee, or 3/4 thrust seating, so as long as actors project I don't need electronic help. Preshow music and SFX is 75% of their use. We sometimes do theater in the round and small musicals and cabarets all of which really need help. If you can see from that photo, the barrel roof and the blackbox itself is where the auditorium used to be. I took that picture from what was the stage... now the lobby. What this means is that sound is fantastic in the N/S direction (the way the photo was taken) but gets swallowed up in the E/W direction.
Theater in the round in that space means that you can hear fine... until you lose sight of the actors' mouths when they turn to the other side. Then you might as well have pillows on your ears. For musicals it's nearly impossible to get a balance unless you amp the actors.
A great example was just tonight. We were doing final dress for a valentine's cabaret tomorrow. My gain and levels are generally low against a single piano. I just need to give the singers' voices a few db of help to balance with the piano.
My shortcoming is that I don't know how to alter the parameters of the box/driver itself to alter things. I'm great at following directions on someone else's design, but altering it to tweak for my own space is beyond my synapses at this point. I would love to change that. I want to have a small arsenal of powered speakers that I can do something simple like hanging them in the grid for audience, tossing one in a pit for a monitor, tucking it under a set piece for a directional SFX, etc.
As you can see from the photos, the furthest a speaker would have to be from anyone's ear is about 15 feet, so you're correct that they don't need 300w or rock concert levels. In fact, I rarely use amplification on actors. Maybe 4-5 times a season. Most plays done here are either 1/4-P, vee, or 3/4 thrust seating, so as long as actors project I don't need electronic help. Preshow music and SFX is 75% of their use. We sometimes do theater in the round and small musicals and cabarets all of which really need help. If you can see from that photo, the barrel roof and the blackbox itself is where the auditorium used to be. I took that picture from what was the stage... now the lobby. What this means is that sound is fantastic in the N/S direction (the way the photo was taken) but gets swallowed up in the E/W direction.
Theater in the round in that space means that you can hear fine... until you lose sight of the actors' mouths when they turn to the other side. Then you might as well have pillows on your ears. For musicals it's nearly impossible to get a balance unless you amp the actors.
A great example was just tonight. We were doing final dress for a valentine's cabaret tomorrow. My gain and levels are generally low against a single piano. I just need to give the singers' voices a few db of help to balance with the piano.
My shortcoming is that I don't know how to alter the parameters of the box/driver itself to alter things. I'm great at following directions on someone else's design, but altering it to tweak for my own space is beyond my synapses at this point. I would love to change that. I want to have a small arsenal of powered speakers that I can do something simple like hanging them in the grid for audience, tossing one in a pit for a monitor, tucking it under a set piece for a directional SFX, etc.
Also, curse you for the Bill Fitzmaurice rabbit hole I am now destined to spend weeks researching 🙂
Thanks for taking the safety stuff seriously.
With regards to your project, for light vocal reinforcement in that space, you could probably do the job with a good pair of 8" 2-way boxes aimed correctly. The idea of 6-8x speakers in operation would result in even more of the comb-filter-y-mess that you've noted with the existing setup. If you wanted to do other things like surround FX etc, though, then I can see the appeal.
Is there any chance you could provide a sketch of the floorplan?
Chris
sounds like it should work but i would suggest using passive enclosures with speakons leading down to a rack of amps somwhere. in my experience this makes troubleshooting (and setup / teardown) easier and gives you more flexibility for setting crossovers and doing different routing.
also with electronic circuits and power plugs up on the rig there is a greater chance of interference. bzzzzzzz
also with electronic circuits and power plugs up on the rig there is a greater chance of interference. bzzzzzzz
So far I've been pretty lucky. I have three-phase delta in the building with two 120v legs serving the theater, so the lighting is all on A-leg and B-leg is dedicated to audio. The lights are also all LED, so no dimmers. I also went as far as to add 22 dedicated 12-ga ground conductors from the grid. Voltage potential from anywhere on the grid to ground is more or less a big zero.
That doesn't help the 200A of 60hz voltage dancing around up there, but so far noise hasn't been an issue.
Edit to add: One of the reasons for wanting to go active is because of the constant re-configuration. I have a digital snake I can put in the grid which is a bit easier than running 8 different 50-foot speaker wires from the tech booth (which is also on wheels so it moves based on configuration in the space). With active speakers I can wheel the booth to wherever I need, plug a Cat6 into one of the nodes on the wall, and then its just a matter of moving and "focusing" speakers toward ears. Then I have discreet digital control over each speaker from the booth depending on how I configure the XLRs from the snake.
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Yes? He says confidently? I have it but it might be on my office computer.
For now, here is a quick sketchup. 60' left to right, 50' top to bottom in this image. The angled walls are hinged so they can fold flat in, flat out, or anywhere in between. For 90% of the time they stay as shown here at about a 30 degree angle. I sometimes put them at 45 degrees for something like a choral performance, or flat against the back for in-the-round. Reference the first photo to see the soft goods hanging.
15' floor to grid, 18' floor to soffit, 27' floor to top of the barrel.
A typical configuration is what you see in the first photo above in my first post. Seating is currently set up toward the bottom of this image and the "pile of furniture" set dressing is between the angled walls near the top of this image.
Mwahaha, my evil plan is working. Well, I guess not really evil. There are many folks on that site that really know their stuff, so my plan for you to learn enough that your BS detector is tuned up seems to be progressing. You might also look for a copy of the Yamaha Sound Reinforcement Handbook, it has some very practical information.
Have fun in the rabbit hole.
I'm not sure about "evil", but I've reviewed some of the BFM designs and found them to be seriously lacking. Recommending them would be a mistake IMO.
Taking some older-model drivers, putting them in larger-than-necessary cabinets and then claiming the +6dB efficiency improvement (in some areas) is world-beating does not count as good loudspeaker design.
Some pitfalls:
--- Increased likelihood of mic feedback
- Take a look at the DR300, for example, and ask why the horns have been orientated that way. It'll take a bit of reading around, but the answer isn't good loudspeaker design.
I'm sure that, when BFM started up, some of those cabinets might have been useful to the DIYer-wanting-to-build-a-PA-system. Modern high-power drivers would keep up with, or beat, the BFM designs in much smaller cabinets, and sound much better doing it.
Chris
Taking some older-model drivers, putting them in larger-than-necessary cabinets and then claiming the +6dB efficiency improvement (in some areas) is world-beating does not count as good loudspeaker design.
Some pitfalls:
- No comparisons with other cabinets at high SPL. We're left to assume higher efficiency will directly translate to more SPL when push comes to shove.
- The frequency response curves are often extremely non-linear.
- Piezo arrays aren't a good idea. Claims of super-wide horizontal dispersion from the tweeters means:
--- Increased likelihood of mic feedback
- Take a look at the DR300, for example, and ask why the horns have been orientated that way. It'll take a bit of reading around, but the answer isn't good loudspeaker design.
I'm sure that, when BFM started up, some of those cabinets might have been useful to the DIYer-wanting-to-build-a-PA-system. Modern high-power drivers would keep up with, or beat, the BFM designs in much smaller cabinets, and sound much better doing it.
Chris
For this project, keeping it simple, it would be easy to build a few boxes with a woofer and compression driver in a horn, kinda like what diysoundgroup is doing. Add in a simple XO, and it would be pretty good for your place, while keeping it at a very reasonable budget, using SBAudience drivers.
Use 10 » woofers for the fronts, maybe 8 » for the sides or behind the audience as fx.
like this: https://www.diysoundgroup.com/home-...ome-theater-series/home-theater/ht-8-kit.html
Use 10 » woofers for the fronts, maybe 8 » for the sides or behind the audience as fx.
like this: https://www.diysoundgroup.com/home-...ome-theater-series/home-theater/ht-8-kit.html
For about 500 bucks you should be able to get a good 8"/1" speaker like the QSC CP8, maybe even Turbosound iQ8. RCF also has nice stuff in this price range.
For background music and voice you also don't need the sub.
I use Dynacord D8A for such a use (and a bunch of passive D8 for stage monitoring) - always surprising what's possible with these litte speakers, sound very good.
I would not go smaller as 8" for LF driver - it's PA after all, the room is big and you maybe just want to use 2 sometimes. Or even 1 to have some background music at the entrance/bar/speaker/.... Probably want to connect just a mic for a little speech. These are so flexible and will last you for many years.
For background music and voice you also don't need the sub.
I use Dynacord D8A for such a use (and a bunch of passive D8 for stage monitoring) - always surprising what's possible with these litte speakers, sound very good.
I would not go smaller as 8" for LF driver - it's PA after all, the room is big and you maybe just want to use 2 sometimes. Or even 1 to have some background music at the entrance/bar/speaker/.... Probably want to connect just a mic for a little speech. These are so flexible and will last you for many years.
they are lucky to have you. ive worked in many large theaters where the tech team doesnt understand this kind of stuff (let alone small non-profit spaces). good luck and keep us posted
I don't have a dog in this hunt, but I have built 4 BFM designs and am working on the fifth.
Curtis, I encourage you to look at the Yamaha book and compare that information to what you see on the BFM forum. If they disagree, ask on the forum, why?. Maybe they do disagree and one is wrong, maybe they really don't, you are just mis-understanding. Gain an understanding of sound. Remember the BS detector? Tune it up. Ask yourself what you want to do. Do you want to design and optimize a speaker or do you want good sound for your application at a diy price that you just wire up and it works? Any system will require tuning to the venue, so don't forget that. If the SLA pro seems like a place to start, build one, try it out, decide if you want more. They are about $100 each, including wood.
Bill's designs are optimized around efficiency in both parts and power consumption. Would I use a BFM system for a 20,000 seat arena? No, I wouldn't. Would I use one for 2,000 where there was limited power available? Yes, I would.
I understand there are people that don't agree with me, and that's fine. We all have our own way of making decisions. It sounds like you have an engineering background, so use those problem solving and analysis skills to choose the best solution for you. It is a rabbit hole, enjoy it.
Rob
Curtis, I encourage you to look at the Yamaha book and compare that information to what you see on the BFM forum. If they disagree, ask on the forum, why?. Maybe they do disagree and one is wrong, maybe they really don't, you are just mis-understanding. Gain an understanding of sound. Remember the BS detector? Tune it up. Ask yourself what you want to do. Do you want to design and optimize a speaker or do you want good sound for your application at a diy price that you just wire up and it works? Any system will require tuning to the venue, so don't forget that. If the SLA pro seems like a place to start, build one, try it out, decide if you want more. They are about $100 each, including wood.
Bill's designs are optimized around efficiency in both parts and power consumption. Would I use a BFM system for a 20,000 seat arena? No, I wouldn't. Would I use one for 2,000 where there was limited power available? Yes, I would.
I understand there are people that don't agree with me, and that's fine. We all have our own way of making decisions. It sounds like you have an engineering background, so use those problem solving and analysis skills to choose the best solution for you. It is a rabbit hole, enjoy it.
Rob
I should also mention some of the parameters/goals here.
First, the $2500 budget is what I have for the entire discretionary tech budget for the year... meaning, if I need a new air compressor, a lav mic, a replacement par light, whatever. I'm approaching the end of the season, so theoretically I could blow the wad on QSCs, but that's not how I roll really.
What I prefer to do is A) DIY stuff so I can get more gear for my dough, B) invite volunteers in to help with the projects and give a mini Master Class (or amateur class as the case may be), C) I bloody love my job and this kind of stuff is fun, and D) biggest reason is my own learning. I would LOVE to know why the waveform of this horn is preferable to that one, or why this driver's T/S parameters will sound better in X cabinet instead of Y cabinet.
The cluster of 4 Yamahas hanging in the middle of the room will need to have new compression drivers in two, and one new woofer, then they can be retained for bigger stuff; SFX, music, whatever. My biggest problem (especially in the round) is that the cluster obviously has to be as far away from everyone's ears as possible. I'm filling a room from a single point, so they have to be up and away. What this does is you get part of the dB from the actor's natural voice (which bounces all over the room and hard to hear) and a significant amount of the dB coming from big speakers that are even farther away that makes the reverb louder. My thought here is more, smaller sources so I'm not pumping 700w through monster drivers. The current setup helps because it amplifies, but it's also amplifying the room reverb. I was thinking that eight 6" cabinets with small horns that serves about 25 patrons' ears would sound better in the space than four 12" cabinets 30 feet away pushing the air in the room enough to service all 150 patrons' ears might be the key.
I'm thinking like a line array, but circular. Sure, phasing might be a challenge, but I would think careful aiming to minimize horn overlap could mitigate it.
Am I crazy?
I'll get that book, A Gordon.
First, the $2500 budget is what I have for the entire discretionary tech budget for the year... meaning, if I need a new air compressor, a lav mic, a replacement par light, whatever. I'm approaching the end of the season, so theoretically I could blow the wad on QSCs, but that's not how I roll really.
What I prefer to do is A) DIY stuff so I can get more gear for my dough, B) invite volunteers in to help with the projects and give a mini Master Class (or amateur class as the case may be), C) I bloody love my job and this kind of stuff is fun, and D) biggest reason is my own learning. I would LOVE to know why the waveform of this horn is preferable to that one, or why this driver's T/S parameters will sound better in X cabinet instead of Y cabinet.
The cluster of 4 Yamahas hanging in the middle of the room will need to have new compression drivers in two, and one new woofer, then they can be retained for bigger stuff; SFX, music, whatever. My biggest problem (especially in the round) is that the cluster obviously has to be as far away from everyone's ears as possible. I'm filling a room from a single point, so they have to be up and away. What this does is you get part of the dB from the actor's natural voice (which bounces all over the room and hard to hear) and a significant amount of the dB coming from big speakers that are even farther away that makes the reverb louder. My thought here is more, smaller sources so I'm not pumping 700w through monster drivers. The current setup helps because it amplifies, but it's also amplifying the room reverb. I was thinking that eight 6" cabinets with small horns that serves about 25 patrons' ears would sound better in the space than four 12" cabinets 30 feet away pushing the air in the room enough to service all 150 patrons' ears might be the key.
I'm thinking like a line array, but circular. Sure, phasing might be a challenge, but I would think careful aiming to minimize horn overlap could mitigate it.
Am I crazy?
I'll get that book, A Gordon.
As I was reading, I was thinking line arrays might actually be very good for you.
Vertical diversion is controlled and as high as the line. Horizontal is wide.
LA also lose a lot less dBs over distance, so helpful in your case.
But I wasn't thinking circular... just two lines, each sides.
At least 16 drivers per side, or 25 would be great.
They are a lot of work though... lots of holes and screws!
Vertical diversion is controlled and as high as the line. Horizontal is wide.
LA also lose a lot less dBs over distance, so helpful in your case.
But I wasn't thinking circular... just two lines, each sides.
At least 16 drivers per side, or 25 would be great.
They are a lot of work though... lots of holes and screws!