Not normally my thing but a Freund has asked me to build some PA speakers for her barn so she can listen to music loud and dance when no one is looking 
Probably needs to be a 2.5 way 15 inch jobbie. Any one point me in the direction of a budget plan set and an all singing all dancing plan set? I've not really got the time to be designing it from scratch for her.
Not to bothered about crossovers, I'll likely use a fusion plate amp.
Ta
Probably needs to be a 2.5 way 15 inch jobbie. Any one point me in the direction of a budget plan set and an all singing all dancing plan set? I've not really got the time to be designing it from scratch for her.
Not to bothered about crossovers, I'll likely use a fusion plate amp.
Ta
How about this Fane three-way reflex design? It's adaptable to a variety of PA drivers.
http://www.4fsc.co.uk/blue-room/Fane Loudspeaker Book, pages 18-25.pdf
http://www.4fsc.co.uk/blue-room/Fane Loudspeaker Book, pages 18-25.pdf
You can find some plans suggestions at speakers manufacturer like Beyma or Eighteensond. Speakerplans forum is also a good resource. Depending on Your audience, We make weddings all the year with 2 horn loaded 15'' subs and 2 15'' coaxials tops for about 150-200 people. Sometimes when we have more audience we bring some powered speakers and place them spaced in the room at corners.
Thanks guys, I'll take a look at the suggested.
To answer the questions, budget is undecided, I said I'd look at a couple of options for her, a cheaper one and a more expensive one. Those options might even be the same speakers, just one actually finished with vinyl , grilles and corner reinforcement etc. Amplification wise she hasn't got any, I build hypex amps so have got an account with them so the likely scenario is a pair of thier plate amps so I'll do crossover duties in there too. Size wise, she's got loads of room and it'll just be her listening to them. Seem hugely overkill I know bit that is what she wants �� A floor stander is better from a form factor point of view though as she doesn't like stands. I could maybe wall mount some smaller speakers though.
To answer the questions, budget is undecided, I said I'd look at a couple of options for her, a cheaper one and a more expensive one. Those options might even be the same speakers, just one actually finished with vinyl , grilles and corner reinforcement etc. Amplification wise she hasn't got any, I build hypex amps so have got an account with them so the likely scenario is a pair of thier plate amps so I'll do crossover duties in there too. Size wise, she's got loads of room and it'll just be her listening to them. Seem hugely overkill I know bit that is what she wants �� A floor stander is better from a form factor point of view though as she doesn't like stands. I could maybe wall mount some smaller speakers though.
FWIW, here are my budget-friendly and all-out options:
All-out one-speaker-per-side PA system:
BMS Coaxial compression driver with 1.4" exit, on a nice big horn.
2x Good 15" subwoofer drivers.
Crossover at around 400Hz.
Tune cabinet to 40Hz, and make sure there's plenty of port area. Give the 15"s a couple of kilowatts each, and another kilowatt for the HF.
Done right, it'll sound HiFi but will go very loud and still sound clean. It's something I'd like to build one day, for sure.
Budget-orientated:
Eminence Beta-10CX, ASD1001 compression driver
Eminence Delta-15
Put the 10" coax in a sub-enclosure, and give the Delta-15 plenty of space as they tend to want a big box to get low.
Add another 15" if cabinet volume and budget allows. Crossovers at 300Hz and 2kHz.
For an installed box, I wouldn't bother with corner protectors, and I'd probably leave the wood bare for the client to decide on finish - they might want to add a splash of colour.
Chris
All-out one-speaker-per-side PA system:
BMS Coaxial compression driver with 1.4" exit, on a nice big horn.
2x Good 15" subwoofer drivers.
Crossover at around 400Hz.
Tune cabinet to 40Hz, and make sure there's plenty of port area. Give the 15"s a couple of kilowatts each, and another kilowatt for the HF.
Done right, it'll sound HiFi but will go very loud and still sound clean. It's something I'd like to build one day, for sure.
Budget-orientated:
Eminence Beta-10CX, ASD1001 compression driver
Eminence Delta-15
Put the 10" coax in a sub-enclosure, and give the Delta-15 plenty of space as they tend to want a big box to get low.
Add another 15" if cabinet volume and budget allows. Crossovers at 300Hz and 2kHz.
For an installed box, I wouldn't bother with corner protectors, and I'd probably leave the wood bare for the client to decide on finish - they might want to add a splash of colour.
Chris
+1 Chris!
The Fane 3 way reflex enclosure design I mentioned earlier would accommodate your budget selection of drivers nicely!
http://www.4fsc.co.uk/blue-room/Fane Loudspeaker Book, pages 18-25.pdf
Full 3 way. Selenium D210 or D220 on HM2525 metal horn, two Eminence Beta 8. Either two Delta Pro 15 ( rock ‘n roll tuning with mid-bass hump) or Kappa 15 LF (pop/disco tuning with LF flat to 40). 10 cubic feet net, with separate mid sub enclosure. Somewhere I have a crossover design - 600 and 3k, LR24 acoustic slopes, switchable full/bi-amp. Originally designed for the Delta’s and that’s what’s in them now (since I am subwoofer-rich). I did try them with the Kappa’s and had the expected result which is better if running subless with bass heavy music.
Sheffield, which is a bit of a drive away.
I think I posted some pictures of the build on my long-running thread in this section, but I don't know if the pictures survived Photobucket's decision to lose 99% of its users overnight.
Plenty of pictures of the finished product on my website in my signature, though.
Chris
I think I posted some pictures of the build on my long-running thread in this section, but I don't know if the pictures survived Photobucket's decision to lose 99% of its users overnight.
Plenty of pictures of the finished product on my website in my signature, though.
Chris
Yeah a bit far
I've never had a look at your site before, ill pop over and have look.
Stefan
Yeah, I stay pretty busy.
Festival season ended a while ago so things are a bit quieter now, although there's an interesting Christmas concert coming up with a 100-strong choir, including live recording. Should be fun.
There are some equipment upgrades coming that will likely alter the prices a little. NDAs are in effect, so I can't say much except that I'll be the first in the UK to get hold of the new amplifiers from a top-end manufacturer
I'm working on some stuff on the recording side of things to keep things going over the quieter months.
Looking around on the website, there are a few bits I need to go through and update - the mic locker has moved on a bit with Sennheiser's anniversary sales.
Chris
Sorry, kind of off topic but Chris, a practical question for you:
Since you've carry varying amount of subs per gig, how do you manage which subs go in parallel and which go in series? Have you managed this within the subs or cabling or how? I believe there is only few long speaker cables from the amp rack to speakers and then some kind of daisy chaining going on at the speakers?
Since you've carry varying amount of subs per gig, how do you manage which subs go in parallel and which go in series? Have you managed this within the subs or cabling or how? I believe there is only few long speaker cables from the amp rack to speakers and then some kind of daisy chaining going on at the speakers?
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I just put more subs in parallel.
Why would I want them in series?
The current sub amp is a Crown MA12000i. While it doesn't do it's best work at 2ohm, it's been enough so far. I'd quite like to have a pair of them running at 4ohm on each side, but there's a certain cost there...
FWIW, when it comes to gigs with all eight subs, I take backup amps. For subs, a pair of Behringer NU6000s do okay.
I once ran all eight from an NU3000 in an emergency, where we had to run the entire stage (PA, monitors, lights) from a single 13A supply 150m away (the generator with a 32A supply died unexpectedly). The idle current of the NU3000 is quite a lot lower than the big Crown amp. I wouldn't be able to hit full power anyway, so just moved the subs across to that and kept a really close eye on power draws for the remainder of the gig.
Chris
thanks! Yes i thought if one amp was used for more than four subs, or if the subs were 4ohm . Anyway, seems best if all connect same ways (parallel) and then bring more amps if load impedance would get too small. Two stacks of four 8ohm subs in parallel (2ohms each stack) could be connected in series to get one 4ohms load
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Good job the drivers are 8ohm, then.
4x 8ohm in parallel gives a 2ohm load.
True, but the amplifiers are 2-channel devices, so I just put one 2ohm load on each channel.
With the drivers I'm using, it's difficult to get enough power at 8ohm to properly drive them. The Crown MA12000i does a good job at 8 and 4ohm, with around 2KW per driver. At 2ohm, it manages somewhere between 1-1.5KW per driver, which is okay but could be better.
If you put two drivers in series on a channel, each would get around 500w, which is okay, but wouldn't get the most out of the speakers.
When it comes to PA systems, it's good to avoid putting drivers in series. With parallel wiring, if a driver burns out and goes open-circuit, the rest of the drivers will carry on working. With two drivers in series, one going open-circuit would result in no signal getting to the other one. With groups of series and parallel, one driver going open or short-circuit can mean that some drivers stop working, or some drivers get extra current (leading to further burn-outs).
Chris
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