So here's the deal...
Next year I will be building my school a PA system as a senior project. I won't actually be starting on it until after the summer but the ASB director has asked me to do a rough budget to present to the ASB to get their okay on the project.
I will have roughly a $5000 dollar budget, I plan to try to work with home depot, parts express, etc to get donations and or discounts so if the design goes over that budget I could probably make it work.
I want to be able to hit incredibly loud levels with this system as our school has a habit of destroying systems by pushing them beyond their limits, I'm thinking somewhere between 140 and 150 dB as a rough guideline.
I've got the low end part of this covered for the most part, I plan to use 4 of the C/E/X PA or similar which I think I can pull off for under $2000.
What I'm not so sure about is the mid-treble range. I want it to have as high dispersion as possible, be almost as loud as the subs (considering the kind of music that will be played its ok if they can't handle quite the same levels), and relatively easy to move around. They should cover 100Hz and up. I plan to build two of them. I'd love to horn load everything for higher spl but I don't know if its better to have direct radiating mids for the just over 100Hz range
I'm not honestly sure what my school has in the way of amps, crossovers, equalizers, soundboards, etc, but I can find that out sometime next week, but I won't worry about that until I know what kind of power I will need.
Can anyone point me in the right direction for the top speakers? If there are any designs or papers I should take a look at let me know.
Any general advice would be appreciated! I don't have much experience in the way of PA systems as I usually do home audio.
Thanks in advance!
Next year I will be building my school a PA system as a senior project. I won't actually be starting on it until after the summer but the ASB director has asked me to do a rough budget to present to the ASB to get their okay on the project.
I will have roughly a $5000 dollar budget, I plan to try to work with home depot, parts express, etc to get donations and or discounts so if the design goes over that budget I could probably make it work.
I want to be able to hit incredibly loud levels with this system as our school has a habit of destroying systems by pushing them beyond their limits, I'm thinking somewhere between 140 and 150 dB as a rough guideline.
I've got the low end part of this covered for the most part, I plan to use 4 of the C/E/X PA or similar which I think I can pull off for under $2000.
What I'm not so sure about is the mid-treble range. I want it to have as high dispersion as possible, be almost as loud as the subs (considering the kind of music that will be played its ok if they can't handle quite the same levels), and relatively easy to move around. They should cover 100Hz and up. I plan to build two of them. I'd love to horn load everything for higher spl but I don't know if its better to have direct radiating mids for the just over 100Hz range
I'm not honestly sure what my school has in the way of amps, crossovers, equalizers, soundboards, etc, but I can find that out sometime next week, but I won't worry about that until I know what kind of power I will need.
Can anyone point me in the right direction for the top speakers? If there are any designs or papers I should take a look at let me know.
Any general advice would be appreciated! I don't have much experience in the way of PA systems as I usually do home audio.
Thanks in advance!
You will need horn loading, and you will need multiple boxes per side. Have a look at the Speakerplans site and forum. Something like the MT122 should do the job, though I'm not sure it gets down to 100Hz. Don't forget to budget in the price of hardware like wheels and handles and suchlike.
4x Punisher Bass horns and 2x X-Tro top cabinets will get 140dB spl with H60 x V40 dispersion.
Speakerstore
Speakerstore
Info on x-over settings here:
Punisher Horn II
But only from 50Hz up so that could be a problem.
Speakerstore
Speakerstore
Info on x-over settings here:
Punisher Horn II
But only from 50Hz up so that could be a problem.
I've been looking at all kinds of different options for the past few hours and I think I'm starting to lean towards the Bill Fitzmaurice DR250. I could build 4 of them and it would be modular enough to use at our football field and also at our small outdoor stage for lunchtime events and the like.
And I really like the C/E/X subwoofer. The size/transportability are good, the drivers are (relatively) cheap at ~$300, its got great output, and it doesn't look hard to build.
Finding info on the BFM tops is tricky without his plans, I can't even find the max power handling right now, but I gather that 4 could hit pretty close to 140dB, and their dispersion is perfect for the stadium with a bit of a tilt upwards on the top speaker in the stack (about 10 degrees). I also can't find anything about the cost...
That first link has a really interesting design, I'll look into it, it does look a bit big. I wouldn't mind the size but I'm not the one who will be handling the system (scary!)
And I really like the C/E/X subwoofer. The size/transportability are good, the drivers are (relatively) cheap at ~$300, its got great output, and it doesn't look hard to build.
Finding info on the BFM tops is tricky without his plans, I can't even find the max power handling right now, but I gather that 4 could hit pretty close to 140dB, and their dispersion is perfect for the stadium with a bit of a tilt upwards on the top speaker in the stack (about 10 degrees). I also can't find anything about the cost...
That first link has a really interesting design, I'll look into it, it does look a bit big. I wouldn't mind the size but I'm not the one who will be handling the system (scary!)
I don't think you are going about this the right way. Making something louder won't stop them destroying it, just more people will suffer hearing damage in the process. Remember, there is no safe exposure time for >115dB.
Get a good compressor/limiter, set it up to give a sensible maximum SPL, put it in a box and lock it. Now it is much harder to damage the PA and peoples hearing.
Brian.
Get a good compressor/limiter, set it up to give a sensible maximum SPL, put it in a box and lock it. Now it is much harder to damage the PA and peoples hearing.
Brian.
Have you built your subs yet? I would suggest the Xoc1 TH-18. The C/E/X 6 Fold 18" TH is quite massive in size and the TH-18 plays louder (what you're asking for). The 6 Fold also requires a bit more timber.
And, yes, with proper gain staging and a brickwall limiter, you shouldn't have problems with blowing drivers.
And, yes, with proper gain staging and a brickwall limiter, you shouldn't have problems with blowing drivers.
Hmmm good idea. Very tempting. I don't think that extra size, timber, and less efficiency is worth it for 8 more Hz. With the B&C 18PS76 (which I ordered) it models ruler flat from 45Hz to 130 Hz with an F3 of about 39Hz. Also the extra height and higher aspect ratio would make it easier to wheel around
I've already ordered all the stuff from PE but it looks like it would be fine because the general layout is similar, it's just the wood thats different. And I could order one less sheet so my surplus budget would go from $300 to about $370
I don't start building until the beginning of the school year, I have 2 class periods to do it.
It's about 3dB more efficient for this driver so my 300 wpc crown amps will be able to do quite a bit more damage. 137dB according to hornresp
Thanks for the tip
I've already ordered all the stuff from PE but it looks like it would be fine because the general layout is similar, it's just the wood thats different. And I could order one less sheet so my surplus budget would go from $300 to about $370
I don't start building until the beginning of the school year, I have 2 class periods to do it.
It's about 3dB more efficient for this driver so my 300 wpc crown amps will be able to do quite a bit more damage. 137dB according to hornresp
Thanks for the tip
Hi kctess5,
Just chiming in with a few questions about power and processing-
Are you bridging the 300 W/ch Crowns one per sub? It might be good to have around 1kW available to each driver for maximun output if possible.
Just curious if you already have amps for the tops as well?
Also, do you already have processing? Going by Bills posted chart of the Dr250 it would be wise to have parametric filters available (just quickly counted six spots) to help smooth them out esspecialy around 10k where the piezos can be a bit unsettling.
Cheers!
Just chiming in with a few questions about power and processing-
Are you bridging the 300 W/ch Crowns one per sub? It might be good to have around 1kW available to each driver for maximun output if possible.
Just curious if you already have amps for the tops as well?
Also, do you already have processing? Going by Bills posted chart of the Dr250 it would be wise to have parametric filters available (just quickly counted six spots) to help smooth them out esspecialy around 10k where the piezos can be a bit unsettling.
Cheers!
It wasn't for us - not a significant enough of a difference. But, the extra SPL from the TH-18 was worth going that route. After even MORE wood for bracing the TH-18, and the little bit extra effort to maneuver them compared to the SS15s, it was the right decision. The 6 Fold would've taken a LOT more wood and been MUCH heavier.
Perfect!
Maybe you mean $370 to $300..? You will need more wood for the 6 Fold after bracing and cone make-up is taken into account.
Glad I could help! Happy building!
Wait a little confused...
If the original plan was to build the FT30 6 folds and I changed it to build the TH-18 wouldn't I need less wood than originally budgeted? Isn't that what you just said?
No thats not quite in the budget. I'm going 1 Crown XLS 1000 DriveCore Series Power Amplifier Flexible for Any Pro Audio Amplification Need 245-500 per 2 subwoofers so one on each channel. I didn't think the relatively small output increase of 3 dB while having to spend $600 more and worrying about power compression, over excursion, etc...
And I'm using the same amps for the tops also. I don't actually have any of the amps but the purchase orders have already been sent pending delivery in August, it's complicated.
I'm getting a dbx DriveRack PA+ Complete Loudspeaker Management System 246-171 to handle limiting, delay, eq, crossover, and all that fun stuff. I'm excited to get to use it actually, it seems quite capable.
I'm using the compression drivers
And now for a rant...
I am not happy with parts express, but they still have a chance to make it up to me, we'll see.
Here's what's been happening.
First of all, I am the only one in charge of this project. I have designed the system, figured out what I need, found a way to source the materials, contacted various companies asking for educational discounts, the list goes on. The ONLY thing that my school (through my ASB director) is doing is telling me what they want, and supplying money when I ask.
Keeping that in mind...
I contacted Parts Express a while back, I got through to Cil, one of the customer service supervisors who I've worked with in the past, and is very helpful. I requested an educational sales discount quotation, so she asked me to send a complete list of the materials and referred me to someone at educational sales. Great, sounds perfect. So I call the person, and after a very brief, somewhat rude conversation she dismisses me because I'm a student and asks for someone in admin. I go over to the ASB director and have her call, she eventually gets through, and tells the person the EXACT same thing that I just had (address...). The person says "okay", and hangs up. No "here's whats going to happen next" or anything, just "okay," hang up.
Kinda wierd, but whatever. On monday, 3 days later, I call back and ask how the quotation is going, as it was 4 days after I sent the information and we don't have any idea when to expect it. Another very brief vaguely rude conversation. She tells me very impatiently that she is working on it and will send it to the ASB director within the hour. I ask if she could just send it to me because I'm in charge and the quote is much more relevant to me. No. She won't do that, she has to send it to the ASB director (presumably because she thinks I'm incompetent, after quite a lot of work to make this whole thing possible). Again, whatever. I go to the ASB director again and ask her to forward me the email as soon as she gets it, and mention how it's weird that this person is seemingly unwilling to work with me, and the ASB director agrees wholeheartedly.
Three hours later I get the forwarded email. And to my complete and utter dismay, it is actually about $100 more expensive than it had been in my non educational cart!
WTF guys! I go over it and it turns out that what happened was that I did get a discount, in fact about $200 worth, but I was required to pay $300 shipping for it (490 pound order, about $4500 worth). Now I had just assumed that because it was over $100 (by a lot!) shipping would be free. But no.
I then called the person back, and I'm like alright first of all you have to work with me, because the ASB director really isn't involved, second of all, why on earth would you charge us more because we are a school. We talked for a bit and basically what I got out of it was two things. First, we could get free shipping, if each order was under 150 lbs. Second, an educational login for the website.
Now let's think this through... I am paying them a lot of money, in fact too much, and because of that, they won't give me free shipping. The way I see it I'm actually saving them money, because if the EXACT same stuff was sent in 45 small orders they would pay quite a lot more than $300 to ship it.
Keep in mind that breaking up the order is kind of a big deal, because we don't just use a credit card. We have to use purchase orders, which have to be cleared with the finance office, etc...
I say whatever again and start to break up the order. This is very tedious as each one has to be over $500 and under 150 pounds to qualify, and I only have 1 shopping cart to work with for 4 orders. I finally get all of the orders printed out, along with a purchase order that is 1 purchase order, with 4 checks written off of it, and write a quick cover letter. And we fax it all to them.
I call back the next day to make sure they got it all. They did, but now the lady is really frustrated with me because even though we can write 4 checks off of 1 purchase order, it still counts as 1 order to them because it's all at the same time. She tells me that she needs to speak with her supervisor to see if they can split up the order or if we need to write 4 totally separate purchase orders (pain in the rear!!!). By this time our schools finances have closed and it's the last day of school. So I tell her that we can figure it all out now but the funds won't be sent until august, and I'm ok with them not shipping until then. And that's where we left off...
Now here's a few things that make no sense to me. I can see hassling someone making a little order, but I am not making a little order. This is over $4000. It seems to me that as a company in a capitalist country, you would want to keep your big customers happy, so that they keep coming back. Therefore, how can splitting up the order POSSIBLY be this difficult for them. I mean really... It's not that hard.
I've just about had it with the person I'm working with at parts express. If she is going to make this more difficult for me, I plan to ask for her supervisor, which I think must be pretty high up the food chain. And if they as a company keep this up, I will take my $4000 order elsewhere, sure it's more work for me, but seriously, there's consequences for not working with your customers. I think it's ridiculous for this person to basically discriminate against me for my age in the first place as I've been very on top of this, and sure I'm 17 now but I won't always be, and I do remember bad experiences.
Thank you for my rant, advice welcome. Sorry that was long
I am not happy with parts express, but they still have a chance to make it up to me, we'll see.
Here's what's been happening.
First of all, I am the only one in charge of this project. I have designed the system, figured out what I need, found a way to source the materials, contacted various companies asking for educational discounts, the list goes on. The ONLY thing that my school (through my ASB director) is doing is telling me what they want, and supplying money when I ask.
Keeping that in mind...
I contacted Parts Express a while back, I got through to Cil, one of the customer service supervisors who I've worked with in the past, and is very helpful. I requested an educational sales discount quotation, so she asked me to send a complete list of the materials and referred me to someone at educational sales. Great, sounds perfect. So I call the person, and after a very brief, somewhat rude conversation she dismisses me because I'm a student and asks for someone in admin. I go over to the ASB director and have her call, she eventually gets through, and tells the person the EXACT same thing that I just had (address...). The person says "okay", and hangs up. No "here's whats going to happen next" or anything, just "okay," hang up.
Kinda wierd, but whatever. On monday, 3 days later, I call back and ask how the quotation is going, as it was 4 days after I sent the information and we don't have any idea when to expect it. Another very brief vaguely rude conversation. She tells me very impatiently that she is working on it and will send it to the ASB director within the hour. I ask if she could just send it to me because I'm in charge and the quote is much more relevant to me. No. She won't do that, she has to send it to the ASB director (presumably because she thinks I'm incompetent, after quite a lot of work to make this whole thing possible). Again, whatever. I go to the ASB director again and ask her to forward me the email as soon as she gets it, and mention how it's weird that this person is seemingly unwilling to work with me, and the ASB director agrees wholeheartedly.
Three hours later I get the forwarded email. And to my complete and utter dismay, it is actually about $100 more expensive than it had been in my non educational cart!
WTF guys! I go over it and it turns out that what happened was that I did get a discount, in fact about $200 worth, but I was required to pay $300 shipping for it (490 pound order, about $4500 worth). Now I had just assumed that because it was over $100 (by a lot!) shipping would be free. But no.I then called the person back, and I'm like alright first of all you have to work with me, because the ASB director really isn't involved, second of all, why on earth would you charge us more because we are a school. We talked for a bit and basically what I got out of it was two things. First, we could get free shipping, if each order was under 150 lbs. Second, an educational login for the website.
Now let's think this through... I am paying them a lot of money, in fact too much, and because of that, they won't give me free shipping. The way I see it I'm actually saving them money, because if the EXACT same stuff was sent in 45 small orders they would pay quite a lot more than $300 to ship it.
Keep in mind that breaking up the order is kind of a big deal, because we don't just use a credit card. We have to use purchase orders, which have to be cleared with the finance office, etc...
I say whatever again and start to break up the order. This is very tedious as each one has to be over $500 and under 150 pounds to qualify, and I only have 1 shopping cart to work with for 4 orders. I finally get all of the orders printed out, along with a purchase order that is 1 purchase order, with 4 checks written off of it, and write a quick cover letter. And we fax it all to them.
I call back the next day to make sure they got it all. They did, but now the lady is really frustrated with me because even though we can write 4 checks off of 1 purchase order, it still counts as 1 order to them because it's all at the same time. She tells me that she needs to speak with her supervisor to see if they can split up the order or if we need to write 4 totally separate purchase orders (pain in the rear!!!). By this time our schools finances have closed and it's the last day of school. So I tell her that we can figure it all out now but the funds won't be sent until august, and I'm ok with them not shipping until then. And that's where we left off...
Now here's a few things that make no sense to me. I can see hassling someone making a little order, but I am not making a little order. This is over $4000. It seems to me that as a company in a capitalist country, you would want to keep your big customers happy, so that they keep coming back. Therefore, how can splitting up the order POSSIBLY be this difficult for them. I mean really... It's not that hard.
I've just about had it with the person I'm working with at parts express. If she is going to make this more difficult for me, I plan to ask for her supervisor, which I think must be pretty high up the food chain. And if they as a company keep this up, I will take my $4000 order elsewhere, sure it's more work for me, but seriously, there's consequences for not working with your customers. I think it's ridiculous for this person to basically discriminate against me for my age in the first place as I've been very on top of this, and sure I'm 17 now but I won't always be, and I do remember bad experiences.
Thank you for my rant, advice welcome. Sorry that was long
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I just meant, more wood to less wood is a decrease in price. I read you comment as an increase in price, but perhaps I read it wrong.
Correct. That's all I was trying to point out above
Good dispersion and high output combined with portability... You need high end midbass specific drivers from reputable premium brands. basically, look for 10-12" midbass options, with ~100+dB sensitivity. They will be Xmax limited to ~100-120hz in most cases at full drive levels in a reflex enclosure, but if you go about it right, you can hit insane levels from a single midbass per side, and a good heavy duty compression driver/horn. This way your "tops" are small and portable.
Keeping up with a well made set of tops built this way, will require some pretty decent bass bins. In the case of bass bins, especially when the ability to use the system in multiple places is involved, you may want to focus on efficiency rather than extension. 40hz for the bottom end is "good enough" really, and you should be looking at proven horn loaded designs that focus on this extension with high efficiency. Reason being, you can't and should not count on having multiple 20A circuits available in all of the potential locations these may be used around the school. The system "needs" to operate inside of a single 20A circuit comfortably. Keep your total amplification at or under "4000W" RMS and you shouldn't have any problems on 20A breaker.
Best of luck, and regards.
Eric
Keeping up with a well made set of tops built this way, will require some pretty decent bass bins. In the case of bass bins, especially when the ability to use the system in multiple places is involved, you may want to focus on efficiency rather than extension. 40hz for the bottom end is "good enough" really, and you should be looking at proven horn loaded designs that focus on this extension with high efficiency. Reason being, you can't and should not count on having multiple 20A circuits available in all of the potential locations these may be used around the school. The system "needs" to operate inside of a single 20A circuit comfortably. Keep your total amplification at or under "4000W" RMS and you shouldn't have any problems on 20A breaker.
Best of luck, and regards.
Eric
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