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Old 1st February 2012, 10:35 PM   #11
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In the long run you maybe better off to hire someone to bring in a PA system for the bigger shows.
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Old 2nd February 2012, 09:49 AM   #12
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I engineer for a few bands (mostly rock) and typically for the bigger venues I make use of a pair of Mackie 1521s (500W each) and a pair of Electrovoice SbA760s (760W each). Through this goes everything, as it allows me to fill out the drums, etc. and get a good balance, allowing the vocals to cut through. If I weren't putting the bass and drums through the PA I would feel comfortable that the Mackies on their own would handle it.

The pub I engineer in has a pair of Fender Cabs (2x15" and a horn) and Audiohead amps, again everything mic'd typically. They like it loud and they like their rock, the system performs day in day out without issue, its been in over 8 years now.

In summary, 1000W with a decent pair of top cabs will be a good starting point, i.e. Peavey Hi-Sys 2RX with a matching amp (PV1.3k, PV2000, PV2600, etc) will get you started with an appropriate mixer that you can then build on, with bass bins, electronic crossover, another amp, etc when funds and demand allow.
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Old 17th February 2012, 07:15 AM   #13
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I also do live sound for many bands in various indoor and outdoor situations. I have a scalable system consisting of up to 12-12" Tapped Horn Subs.In smaller rooms I can easily use 2 per side which is a 32"x30" footprint and knock your teeth out of your mouth with some kick drum.Tops are 2- Double 12" and 8-single 12" horn loaded boxes with 1" Compression drivers on Elliptical and vertical horns. The smaller 12" top boxes can be vertically line stacked. While not a true line they do couple quite well especially for those big outdoors events.Sub drivers are Eminence Diffinimax 12" and Mid Drivers are Eminence 12" Delta-Pros12A's. Horn drivers are a mix of BMS and Selenium 1".Amps Crown Ma2400s subs and mids Micros 1200s Horns. Wedges EAW 159zi run with QSC PLX-3002's.All the Pa boxes are roll yer own.

You can probably build 4 of the subs and a pair of tops for under $3000.00. Thing is the rig will perform well and hits pretty hard. Good for Clubs up to 2000-2500 sq. ft. I add additional subs and tops as the venues grow.I can do 50 x 120 ft building with 8 subs and 2 sets of double tops and it's still hitting hard at FOH 50ft back from the edge of the stage.
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Old 24th February 2012, 12:59 AM   #14
mdocod is offline mdocod  United States
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From what I can tell, the lowest frequency you intend to put through the speakers is going to be from the guitars and if you have bass vocalists? That would be ~80hz for the bottom end unless you are tuning lower than normal correct?

I don't see any reason to approach these PA speakers from a uber-low frequency-capable standpoint. Unless I missed something? Sounded like you do not intend to run the bass guitar or drums through these PA speakers right? I'm confused about why everyone is suggesting big bass units. 80 hz is pretty manageable and is a common x-over point from "main" PA speakers to the "subs" in a system.

You're performing in relatively near-field venues (right?), with your audience probably relatively close to your performing position and close to your speakers. I would want a wider dispersion design, not a "far-field" design. I would not do a "typical cheap PA" 2-way 15" crossed too high to a narrow horn, I would personally do either a sort of short-semi-line array of of either 2-4 x 10", 3-6 x 8" or 6-12 x 6" drivers per side crossed to a horn on top with a wide dispersion pattern, using an active X-over in the 1500-2000hz range (smaller drivers will allow for higher x-over point)... OR, a 3-way using 1-2 x 15" drivers, and either the phenolic selenium "midrange" compression driver (D250-X) or a ~8" midbass. Such an implementation would probably be most cost effective with a passive x-over between the mid and HF drivers to reduce the number of amplifiers required. I'd still use an active x-over for the lower x-over point (which would be in the 500-1000hz range on the 3-way design).

Easiest way to deal with the active x-over is to buy a pair of 2 channel amps with built in x-over capabilities, and use one 2 channel amp per speaker, one channel for the highs and the other for the lows on each side.

Under $100 per cab is not likely. The lowest cost compression driver I would suggest is the D220Ti, and that's $50 for the raw driver. I would suggest the HC23-25 or something similar for the horn itself (~$12). Dayton PA255-8 10" drivers are $44 each, assuming just 2 per box, that brings driver cost alone up to $150 per cab. Best case scenario I'd guess they would wind up around $250 per cab with corner treatments, handles, a pole mount, and some sort of decent carpet or paint finish.

I'd suggest Crown XLS amps since they include a built in adjustable x-over which can be used for either your crossover point or your high pass filter, whichever is more convenient based on what other equipment you intend to use or already have. They have a pretty good track record of reliability and are popular even in very large professional venues. Add up woofer RMS power ratings, and try to get twice that much amplification power.
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Old 24th February 2012, 05:41 AM   #15
mdocod is offline mdocod  United States
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If the budget absolutely must stay low, you might consider these woofers: 10" Ribbed Paper Cone Woofer Speaker 299-284

They aren't PA gear... Think of them like a stepping stone. Spend some money on building some rugged road worthy boxes with 4 or more of those woofers per box and a nice horn on top. They may prove surprisingly effective, especially if the specs are true. I'd build the box sealed with drivers in a vertical line, give them around 2 ft^3 per driver. Leave room on the front baffle for a port to be built in at a later date (when you upgrade to PA woofers with a lower Qts, when money allows).

Worst thing that can happen is they burn out or perform poorly and have to be upgraded prematurely. I think it's a worthwhile gamble personally. Their main drawback is going to be very low power handling, which will limit your maximum SPL by about -10dB compared with an equal number of well made 10" pro sound drivers.

Last edited by mdocod; 24th February 2012 at 05:44 AM.
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Old 26th February 2012, 12:26 AM   #16
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I am not sure if those could hold up very well in a PA application.
But, I have been simulating them in Winlsd in some closed boxes and 8 of them in one box can yield some very impressive results.

I had just gotten six of these to populate my old Sunn 610 Cabinet,

Pyle Pro PPA10 10" PA Speaker 292-214

They seem to be very stout drivers for the money although they are 10's.
I Had done some open air response measurements but I can't seem to find them so I will have to do it again in a few days and then I will post them for you.

These have a pretty good response for a P.A midrange up to about 4khz (I think).
But I will redo the plots and post them for you the only one I do have I had printed off, So, I at least have that one.
They also exhibit a good THD curve as well.
I have not yet mounted these drivers, But, I will be trying them in a couple of different boxes before they are put in their final destination.

I also had a pair of these in my Sunn 215 cabinet,

http://www.mcmelectronics.com/produc...-1880-/55-1880

I used to run an Ashley FTX-2000 bridged on them for a 1000 watts never had a problem with them.
They are everything that the specs say and more as the performed and sound great.
I used to joke with my friend that I would put them up against his Cerwin Vega's any time only his were 18's in which did come apart every once in a while.

My MCM's eventually where swapped into some EV three way road cased P.A. cabinets and I took the ailing Altec Lansing drivers that the voice coils had torn from the cones,Fixed them and put those into the Sunn 215.
Those still work but I wish I still had those MCM's.

The price hasn't changed much from back then (1995), but when I got them the invoice had read 109.95 for each one.
What a deal and great drivers to boot !!!

They also have 18" and 21" versions of these woofers but I have not used those, But I wouldn't be afraid to try, Knowing the experience that I had with the 15" driver.

I thought that ole' Sunn cabinet was going to spilt at its seams with those drivers !!!


jer

Last edited by geraldfryjr; 26th February 2012 at 12:54 AM.
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Old 26th February 2012, 09:24 AM   #17
dangus is offline dangus  Canada
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I was going to suggest the Eminence Delta Pro 15", but prices have gone up a lot since I bought mine. Still, they're very efficient, which means loud. You could do worse than combine one of those with the PSD2002 compression driver and some horn.

On the other hand, persistent searching could turn up bargains on used gear. Call up local rental outfits, ask if they can suggest other places or people. There could be some dude retired from the business with a garage full of gear. Do be aware that absolutely _anything_ could be wrong with used gear... missing parts, modified crossovers, inappropriate repairs or replacement parts.

Maybe the very best idea is to rent stuff first and get a feel for what you really need.
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Old 26th February 2012, 07:17 PM   #18
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Despite suggestions that I pick up and repair some used gear, part of the point of this is to gain the experience of building the cabs. I realize repairing used gear is cheaper than building new cabs from scratch, which is of course cheaper than buying new. In this case, I have decided to up my price range to $600-$700 for the whole project. Let me know how realistic that number is.

Not worried about low end response for the acoustic guitars.

My friend has a pretty sweet 10 channel PA head (800 watts) that sounds great, will use that for now until I can build my own tube PA haha, so for now let's focus on JUST the cabs.

Preferred config would probably be 4x(15+horn) or 2x(2x15+horn) but this is simply due to convention and portability. The first config would probably be preferable in terms of loading and portability. Will certainly consider other configs though, such as a 4x10 or 1x18, but something like a 2x18 is probably a bit too big haha. Again, not worried about bass response so much here.

What 15 and what horn? What cab dimensions? What xover freq? Ported? Front loading or rear loading speakers? What power handling per cab? How to deal with different power handling for woofer and horn? There HAS to be a project like this out there already haha.

Thanks to everyone!!!

Last edited by foul_owl; 26th February 2012 at 07:23 PM.
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Old 26th February 2012, 07:29 PM   #19
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Alright, this one looks pretty damn good, thanks for the suggestion!

MCM Audio Select 15'' Die Cast Professional Woofer - 400W RMS 8ohm | 55-1880 (551880) | MCM Audio Select

So maybe 4x(15+horn) using that speaker?

I might even be able to go SLIGHTLY lower end than that speaker perhaps? (Maybe $90 for the 15", $40 for the horn, then ~$130 for the rest of the materials for all four cabs?)

Holy crap I just read a review for those 15s. I want to throw those into a bass cab now haha and I don't even play bass :P
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Old 26th February 2012, 10:12 PM   #20
mdocod is offline mdocod  United States
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Hello foul owl,

Questions:

Is the $600-700 for just cabs (materials/drivers), or does that need to include amplification? (reason I ask is, I suggest no less than around $600 worth of bi-amplification for the project if buying new).

How "deep" is the listening audience usually? Are you usually on an elevated stage or at ground level?

-----------

Considerations:

The MCM drivers looks nice but I'd say a bit spendy for what you are getting. The Dayton brand 15" pro woofer is only $75, on paper it looks every bit as good to me. I would say though, that neither the dayton or the MCM are really optimized for your frequency range needs. Both have more bottom end extention capability than you need, which could be traded for better efficiency with different driver selections.

I don't suggest doing 2 horns per side (unless it's a 3-way system). Many companies have decades of research into their latest pro-sound cab designs that can effectively couple the high frequency horns into acceptably "proper" line-source arrays... This being your first build, I would not suggest venturing there for the high frequency. Too much complication with too much opportunity to make things sound worse. On the other hand, achieving a reasonably functioning line source for the low frequency is not so complicated. Driver center-to-center spacing and x-over point are the primary considerations. Then roughly match the compression horn dispersion pattern at x-over point to the dispersion of the line and you have a pretty good shot at making a nice multi-woofer PA cab. Bi-amplification will then allow an easy level adjustment to match the point source horn output to the line source output. (mixing point and line source will create some level balance issues between the highs and lows, but that's why you want to bi-amp this).

It's my understanding that coupling multiple 15" drivers into a reasonable functioning line source requires a pretty low x-over point to achieve. ~800hz is probably about as high as I would venture. Such a low x-over point complicates things, because it necessitates the use of either a 3-way system, or moving up to an expensive 2" size compression horn and sacrificing the top octave. Both of those options can work very well, though I think personally, I'd aim for smaller drivers in the line in order to eliminate these complications.

A lot of the cheaper pro-sound cabs out there use the dual 15" and horn configuration, but do not adhere to driver coupling/blending issues very well. The point is that there are plenty of "commercially" made cabs out there that ignore the considerations I am sharing above, and still "work" reasonably well. Point being, the considerations above are ways to make things sound better, but aren't absolutely required to make things work.

------

edit in: forgot to mention... Try not to concern yourself too much with the power handling of the horn driver. Very roughly speaking, in your case, your woofers will be covering ~5 octaves, While the horn tweeters only cover ~3 octaves. The vast majority of the musical content of live instrument and vocals is in those bottom 5, rather than those top 3 octave. Top that off with the fact that even a single horn is still going to be more sensitive than 2x15" or 4x10" woofers (or some other combination) it will achieve equal SPL for probably 1/4 to 1/2 the power costs as the woofer array anyways. When you factor in the lower program demands and the higher efficiency, I'd say it's perfectly reasonable to have your compression horn only capable of about 1/10th to as little as 1/20th the power handling of your woofer arrays. Also, if you bi-amp you will have very controlled steep roll-offs that will further protect the compression tweeter.

Eric

Last edited by mdocod; 26th February 2012 at 10:38 PM.
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