Alright, here is the band setup. Metal band, two guitar players, each guitar player has a 100 watt tube amp and a full stack, bass is a mesa 400+ in a 4x10 and a 1x15. We play pretty loud, but try to keep things manageable. We have tried turning down, but the problem there is that the drums just don't have the right punch and attack as when louder. At any rate, the volume level is comparable to bands in the same category. So not looking for replies here about turning down or whatever. We all wear earplugs when playing of course.
This PA would be used for 4xvocals + 2xacoustic guitars + violin + cello. Violin, cello and probably 1 or 2 vocals at a time for louder parts, quieter parts would be all 4 vocals + acoustic guitars + violin + cello.
Anyway, onto my question! I am considering a DIY tube PA head, but due to the high number of channels, I think something solid state might be easier. I would like to build an appropriately powerful 8 channel PA head, but more importantly, first I would like to build appropriately powerful speaker cabs.
So first of all, what sort of wattage do you think would be good? I was considering 400 watts total (200 per channel) but of course if you think more is needed, let me know.
For the cab, I was thinking two cabs (would more at lower wattage sound better?), each cab has a horn and 2x15 speakers. Or even better, a cab with just a 15" and a horn.
I was thinking two of these:
Goldwood GW-1538/PA 15" Guitar Speaker 290-394
That gives a rating of 280 watts per cab. Not sure how the power rating works with the crossover and horn involved.
Basically, here are my questions.
1. How much power would you estimate I need for this PA?
2. What sort of cab configuration do you think would sound good? It would be nice to consider budget (less than $100 per cab), midrange ($100-$200 per cab) and high end (more than $200 per cab) Basically, what speakers should I get from parts express haha?
3. How to calculate how much power goes to the horn when using a crossover. My guess would be once you are fully in the horn's frequency range, ALL the power goes to it, but I can't find horns rated high enough...(200 watts per cab at least, right?) It would be nice if the impedance of the cabs was something tube compatible (4,8, or 16)
Anyway, how would you design this PA system?
(For the head, I might just borrow a solid state PA head from a friend, but ideally I would love to have an 8 channel tube preamp/mixer => 300 watt stereo tube power amp powered by 4xKT120s haha (but maybe not enough power?) )
Thanks!
This PA would be used for 4xvocals + 2xacoustic guitars + violin + cello. Violin, cello and probably 1 or 2 vocals at a time for louder parts, quieter parts would be all 4 vocals + acoustic guitars + violin + cello.
Anyway, onto my question! I am considering a DIY tube PA head, but due to the high number of channels, I think something solid state might be easier. I would like to build an appropriately powerful 8 channel PA head, but more importantly, first I would like to build appropriately powerful speaker cabs.
So first of all, what sort of wattage do you think would be good? I was considering 400 watts total (200 per channel) but of course if you think more is needed, let me know.
For the cab, I was thinking two cabs (would more at lower wattage sound better?), each cab has a horn and 2x15 speakers. Or even better, a cab with just a 15" and a horn.
I was thinking two of these:
Goldwood GW-1538/PA 15" Guitar Speaker 290-394
That gives a rating of 280 watts per cab. Not sure how the power rating works with the crossover and horn involved.
Basically, here are my questions.
1. How much power would you estimate I need for this PA?
2. What sort of cab configuration do you think would sound good? It would be nice to consider budget (less than $100 per cab), midrange ($100-$200 per cab) and high end (more than $200 per cab) Basically, what speakers should I get from parts express haha?
3. How to calculate how much power goes to the horn when using a crossover. My guess would be once you are fully in the horn's frequency range, ALL the power goes to it, but I can't find horns rated high enough...(200 watts per cab at least, right?) It would be nice if the impedance of the cabs was something tube compatible (4,8, or 16)
Anyway, how would you design this PA system?
(For the head, I might just borrow a solid state PA head from a friend, but ideally I would love to have an 8 channel tube preamp/mixer => 300 watt stereo tube power amp powered by 4xKT120s haha (but maybe not enough power?) )
Thanks!
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What your thinking you need and what your really need are worlds apart. I am going to say it you guys need to turn down! The days of full 100 watt guitar stacks are long gone. Yes you may still see them on some big stages but in reality many of them are just for show. Sometimes behind the stack is small combo amp or even no amp at all.
A PA to keep up with what you want and are doing would be at the very least a REAL double 18 cabinet and a solid double 12 x 2 inch top box per side ran tri-amp with about 2000 watts per double 18, 1200 per side for mids and 300 to 400 on the horns.
Stage monitors that would have the guts to stay on top of your stage volume in addition to your ear plugs would be another story.
A PA to keep up with what you want and are doing would be at the very least a REAL double 18 cabinet and a solid double 12 x 2 inch top box per side ran tri-amp with about 2000 watts per double 18, 1200 per side for mids and 300 to 400 on the horns.
Stage monitors that would have the guts to stay on top of your stage volume in addition to your ear plugs would be another story.
We have full stacks on guitar, but the reason I like full stacks is having more speakers higher up so that I can hear what I am playing. Usually the places we play will have a decent PA for vocals, but no way to mic up cabs, no stage monitors, and no time between sets to mic up anything and balance the levels in the monitors for what people want. The band usually sets their levels, and the sound person sets the vocal levels, and that's that.
Now for practicing, yes we have full stacks, but we don't run master volumes very high. I would say, for example if I was to use someone's 5150, we would run the volume for that at about 11 or 12 oclock, perhaps even lower. But of course that could mean anything in terms of decibel levels. Probably ~115-120 db at where I am standing?
Maybe it would be a better idea if I measured min, max, and approx average decibel levels next band practice? (Ill measure at various places around the room)
You know what I'm saying though about drum attack? For example, if I told my drummer to play softer, the tone of every single drum would not be the same. Personally I don't care about turning down, its just a matter of being heard over the drummer. Although I do like having speakers up in the air behind my head. (bottom cab could just be an empty box)
Haha yeah and I know the walls of stacks are usually fake. We are never planning on playing well funded shows though. (see my comment about the house sound systems at places we play) Usually it's a DIY warehouse, and there may or may not even be a sound guy (thus the need for our own PA haha although we would rather not bring a PA on tour, but it's better than playing a show without one!)
Now for practicing, yes we have full stacks, but we don't run master volumes very high. I would say, for example if I was to use someone's 5150, we would run the volume for that at about 11 or 12 oclock, perhaps even lower. But of course that could mean anything in terms of decibel levels. Probably ~115-120 db at where I am standing?
Maybe it would be a better idea if I measured min, max, and approx average decibel levels next band practice? (Ill measure at various places around the room)
You know what I'm saying though about drum attack? For example, if I told my drummer to play softer, the tone of every single drum would not be the same. Personally I don't care about turning down, its just a matter of being heard over the drummer. Although I do like having speakers up in the air behind my head. (bottom cab could just be an empty box)
Haha yeah and I know the walls of stacks are usually fake. We are never planning on playing well funded shows though. (see my comment about the house sound systems at places we play) Usually it's a DIY warehouse, and there may or may not even be a sound guy (thus the need for our own PA haha although we would rather not bring a PA on tour, but it's better than playing a show without one!)
Gee, I bet your vocals are muddy and inaudible like the other amateur bands I've heard. You've got to understand you're performing for the audience, not yourselves. You have too much music on the stage for yourselves. Jeff Beck last spring didn't have any stacks behind him, but he had about 10000 watts to the sides and in front of the stage. All the big watts went into the bass, he wasn't blasting my eardrums with treble. But I could understand the words when the girl bass player sang.
And if the drummer is not loud enough, put him up front and blow off the mikes. When I played a drum in high school you could hear me from the press box at the top back of the stadium. Of course our bass drum was 36", not one of these wimpy drums the bar bands play. When 24 of us played a drum hit you could hear the echo bounce off the freeway retaining wall a mile away 2 seconds later. If your actually going to buy the 4 or 5 drum mikes it takes to do it right, make sure your power is 1.3kw peak or more. Drum and piano take tons of power, much more than mushy guitar.
I don't understand the problems of playing in bars, but I understand cheap PA gear. I got a PV1.3K for $55 and have put $120 in parts in it. By the time I convert the stupid speaker crowbar PCB burner into a O.T. meltdown detector and speaker disconnect relay, parts will be $150. If I were running a band on a shoe string now, I'd get a pair of burned out Peavey SP4's, replace the speakers myself, and set them to the side of the stage. Else a pair of SP2's on 6' stands and a 218 subwoofer, but that takes three channels of amp and takes longer to set up. I'd buy a burned up Peavey or crown amp of 800-2000 watts and repair it. All new electrolytic caps in it, speaker disconnect relay if is is not a modern CS800s or x, plus whatever else is toasted, Dual banana jack or nutrix speaker plugs, no 1/4 phone jacks. The only 1/4 phone jacks you want on the stage are the guitar inputs: no high powered 1/4 plugs to burn out your amp inputs. Then I would not buy or power stage monitors. I would buy an FM radio transmitter from a hobby supplier, and wear FM radios and Plantronics telephone gear in one ear for the monitor feed. That is if you can afford a sound man (woman? any girlfriends, siblings? parents?) to set the balance after you start. I'd use cabled microphones. There are lots of cheap radio mikes on Craigslist, which probably means they don't work well enough anymore. The one at church sure doesn't work. Probably just bad nicad batteries, but diy radio transmitter repair is not legal.
And if the drummer is not loud enough, put him up front and blow off the mikes. When I played a drum in high school you could hear me from the press box at the top back of the stadium. Of course our bass drum was 36", not one of these wimpy drums the bar bands play. When 24 of us played a drum hit you could hear the echo bounce off the freeway retaining wall a mile away 2 seconds later. If your actually going to buy the 4 or 5 drum mikes it takes to do it right, make sure your power is 1.3kw peak or more. Drum and piano take tons of power, much more than mushy guitar.
I don't understand the problems of playing in bars, but I understand cheap PA gear. I got a PV1.3K for $55 and have put $120 in parts in it. By the time I convert the stupid speaker crowbar PCB burner into a O.T. meltdown detector and speaker disconnect relay, parts will be $150. If I were running a band on a shoe string now, I'd get a pair of burned out Peavey SP4's, replace the speakers myself, and set them to the side of the stage. Else a pair of SP2's on 6' stands and a 218 subwoofer, but that takes three channels of amp and takes longer to set up. I'd buy a burned up Peavey or crown amp of 800-2000 watts and repair it. All new electrolytic caps in it, speaker disconnect relay if is is not a modern CS800s or x, plus whatever else is toasted, Dual banana jack or nutrix speaker plugs, no 1/4 phone jacks. The only 1/4 phone jacks you want on the stage are the guitar inputs: no high powered 1/4 plugs to burn out your amp inputs. Then I would not buy or power stage monitors. I would buy an FM radio transmitter from a hobby supplier, and wear FM radios and Plantronics telephone gear in one ear for the monitor feed. That is if you can afford a sound man (woman? any girlfriends, siblings? parents?) to set the balance after you start. I'd use cabled microphones. There are lots of cheap radio mikes on Craigslist, which probably means they don't work well enough anymore. The one at church sure doesn't work. Probably just bad nicad batteries, but diy radio transmitter repair is not legal.
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Depends greatly on the PA being used at the venue. Thus my question.
Vocals are crust punk style but this isn't a forum for debating which genre of music is better...
No ****.
Too much music? Do you mean too many instruments or levels set too high? Every other metal band I have seen perform in underground venues sounds great (or can sound great!) at similar levels, but like I said, it depends greatly on the PA they are using. Thus, I would like to build some PA speaker cabs that would work for what I want, using the speakers found on partsexpress, for the best price for the sound given my approximate budget. That is the goal here.
The drummer is plenty loud enough, thus the need for big guitar and bass amps. And like I said before, if the drummer plays quieter, you don't get the same sound out of the drums, and again, this isn't a forum for debating genre preference, it's a forum for building audio projects.
I don't know how common it is to find the burned out speakers you mentioned, but I wouldn't mind building from new parts, even though it might cost a little more.
Thanks for the help!
If I were in your position I'd be looking for some name brand 'bass bins' with 18" drivers in them that I could recone or replace the drivers in before I started building something from scratch to put in service under the conditions you describe. You're looking for spl & bottom end impact in the 30-40 Hz range for the genre of music you play- You need a TON of bottom end and vocals to keep up with those guitar stacks.
Unless you really know what you are doing you are not gonna get good results building regular boxes. This is one of those deals where there ain't a real cheap way out of your delimma. There are some really good designs out there for DIY bass bins- but the investment in tools and materials (not to mention the skills) to do a professional job building them is pretty expensive.
Unless you really know what you are doing you are not gonna get good results building regular boxes. This is one of those deals where there ain't a real cheap way out of your delimma. There are some really good designs out there for DIY bass bins- but the investment in tools and materials (not to mention the skills) to do a professional job building them is pretty expensive.
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I just re-read the OP- if you are not gonna run the bass and drums through the PA then indianjoes post above is spot on. I'd be looking for some cabinets with a 15 & horn in them- probably 4 cabinets (two on each side) and maybe an 18" sub box ought to do what you need. Peavey, Electrovoice, JBL etc.. I recently picked up a pair of older EV cabinets like that for $400 on craigslist- they are in great shape and they really put out. QSC amps are decent and can be found for sale (craislist etc..) for reasonable prices.
Getting a speaker right is a matter of design & testing, all of which are expensive & take time. On the other hand speaker repair is not too hard for an amateur. Buy some drivers, replace some capacitors, it's easy. We have a musician's resale shop near the Peavey dealer that sells old band gear. They buy it working for half of what they sell it for, gives me some sort of floor on price idea. Craigslist is your friend, kiji in canada and more so searchtempest.com which will search all the CL catagories (musical instruments, electronics, free, furniture) for the phrase you put in within a distance you choose. Or get some part numbers and post your own ad, looking for blown up gear. The box is what you want, new drivers are a commodity. (See tubesandmore.com for example) I may have overemphasized horns in my previous post, I am a keyboard player and need horns. Guitar-bass-vocal bands with no drums on the PA don't need anything smaller than a 12" speaker, with lots of 15" and 18" speakers for the guitars and bass. I think these should be to the side and front of the stage for the audience. I think the band blend should be in your ear, the way the pros are doing it now. But you don't need all that business band radio stuff with wireless mikes for a non-pro show.
Reducing the sound level on stage is important to proper miking of the vocal. However distorted the vocalist is sounding, you don't want the drum and guitars feeding in there. That is why I think stacks behind the band are a visual prop, not proper sound equipment. That is why I suggest putting the drummer away from the microphones. Electric guitars and bass are not an actual problem, the stacks are.
All you need for level setting is someone on the audience wearing a mike and a FM radio transmitter, the mixer board doesn't have to be out there. The delay from an audience mike can drive some musicians nuts, but somebody in the band could probably listen in and ride the levels. I'm thinking of Ron Pizzarra's band, where the keyboard player is obviously changing the mix during and between songs on a mixer to her side.
As far as power, a blown up 1300 watt amplifier costs about the same as a blown up 200 w amplifier. You'll pay more in output transistors the higher the watts, about $8 each pair. A 200w amp has about 4 transistors, this PV 1.3k has 10 O.T.s, and 4 driver Ts. New rail caps for a 1.3k are about $160 as designed (4 <70 mm 10000 uf) or $48 fooling around the way I do it (8 4700 uf). Rail caps need to be under 15 years (one failed on this amp at 14 years) or 2000 hours. I've looked at some schematics on solid state. I understand some Peavey and Crown stuff. I don't understand the grounding scheme in QSC. Behringer doesn't give away schematics and part number crosses, so they are on my **** list. Stay away from dead amps with switcher power supplies in the beginning, they are for experts. It is hard enough making a transformer amp work in the upper power ranges. Read about light bulb boxes and debug techniques on solid state, saves a bag full of blown (second time) output transistors.
Bottom line, I think repair is easier than scratch building. But I'm not working, so I have an hour or two a day to play with the internet. I love it. Scored a SM27 condenser mike last week for $80, been looking for something that good for my piano for 42 years.
Reducing the sound level on stage is important to proper miking of the vocal. However distorted the vocalist is sounding, you don't want the drum and guitars feeding in there. That is why I think stacks behind the band are a visual prop, not proper sound equipment. That is why I suggest putting the drummer away from the microphones. Electric guitars and bass are not an actual problem, the stacks are.
All you need for level setting is someone on the audience wearing a mike and a FM radio transmitter, the mixer board doesn't have to be out there. The delay from an audience mike can drive some musicians nuts, but somebody in the band could probably listen in and ride the levels. I'm thinking of Ron Pizzarra's band, where the keyboard player is obviously changing the mix during and between songs on a mixer to her side.
As far as power, a blown up 1300 watt amplifier costs about the same as a blown up 200 w amplifier. You'll pay more in output transistors the higher the watts, about $8 each pair. A 200w amp has about 4 transistors, this PV 1.3k has 10 O.T.s, and 4 driver Ts. New rail caps for a 1.3k are about $160 as designed (4 <70 mm 10000 uf) or $48 fooling around the way I do it (8 4700 uf). Rail caps need to be under 15 years (one failed on this amp at 14 years) or 2000 hours. I've looked at some schematics on solid state. I understand some Peavey and Crown stuff. I don't understand the grounding scheme in QSC. Behringer doesn't give away schematics and part number crosses, so they are on my **** list. Stay away from dead amps with switcher power supplies in the beginning, they are for experts. It is hard enough making a transformer amp work in the upper power ranges. Read about light bulb boxes and debug techniques on solid state, saves a bag full of blown (second time) output transistors.
Bottom line, I think repair is easier than scratch building. But I'm not working, so I have an hour or two a day to play with the internet. I love it. Scored a SM27 condenser mike last week for $80, been looking for something that good for my piano for 42 years.
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I just spent 25 minutes typing up a reply and I was logged out before I could post it...
Needless to say, this is what I was going to say in a nutshell:
1. Pick an amp to repair carefully! My Crown Comtech 400 has 16 output transistors (as I remember) and 8 driver transistors. Each output transistor costs $8!
2. Acoustic balancing is incredibly important! I've heard tons of bands where the vocalists have been overpowered by tons of guitar amp wattage! This really kills the experience and in my opinion makes the difference between a small-time band and a big-time band. If you have to, have a member of your group sit in the audience and see how your music sounds from their perspective.
Good luck!
Needless to say, this is what I was going to say in a nutshell:
1. Pick an amp to repair carefully! My Crown Comtech 400 has 16 output transistors (as I remember) and 8 driver transistors. Each output transistor costs $8!
2. Acoustic balancing is incredibly important! I've heard tons of bands where the vocalists have been overpowered by tons of guitar amp wattage! This really kills the experience and in my opinion makes the difference between a small-time band and a big-time band. If you have to, have a member of your group sit in the audience and see how your music sounds from their perspective.
Good luck!
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.
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.
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.
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.
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.
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.
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.
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.
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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/product/MCM-AUDIO-SELECT-55-1880-/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
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/product/MCM-AUDIO-SELECT-55-1880-/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
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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.
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.
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!!!
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!!!
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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
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
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.
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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
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
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