Looking for a PA System

[NateTTU]

My brother-in-law really likes my statement speakers and wishes to build some speakers for his band. I found a couple of promising designs at PE such as the blue wonders and magna cum laude. However, it looks like the drivers have been discounted for both designs. Does anyone know of any other designs out there that would give him a very high end sound but at ridiculous volumes? We both love the laid back sound of the statements and I think he would be looking for something similiar. I find most concerts give me a headache because of the blistering highs. I'm thinking his budget would be around $600 for a pair or so.

Thanks,
Nate

[ThomasW]

The 'needs' of a system used for PA work are vastly different than those for HT/home audio.

Decades ago the Grateful Dead ran a modified HT system for PA use, thing is it takes triple or more the number of boxes to do the job.

With his rather modest budget he should stick to compression drivers/horns and high efficiency ported boxes..

[augerpro]

How about a Faitalpro 12PR300 mated to a B&C DE10 and ME10 horn ? Use some 30ppi foam in the horn ala Geddes. usspeaker has the woofer for $149, the complete speaker (drivers, XO, and box) should come in around $550 a pair.

[NateTTU]

I was hoping someone might point me to a different site with more designs geared for this application. I only know of this site, PE, and zaph. I know this site is definately more geared to the home aspect.

I've never made a design, only built one already created so I'm not sure what I would do with the drivers listed. I definately agree though, it would have to use compression drivers and horns. He is currently looking at a pair of JBL PA speakers for about $700 and was hoping to get some good performance for that small of budget from DIY. If there really isn't anything out there then I can report that back and maybe he would want to design his own.

Thanks for the input.

Nate

[augerpro]

Can't think of any sites that do PA stuff, except PE, and their designs are pretty...cheap. How would these be used?

If your B in L is interested, I could help him with the design. When he has the boxes built, send one over to me and I can come up with the crossover. This particular design has been in the back of my head since a friend from work was looking to replace his old Cerwin Vega's about six months ago. He's on disability now so he can't afford it, but it still interests me. Let me know if you are interested.

[davey_m]

Here's a site where you can learn more about PA speakers, with some construction plans:

http://speakerplans.com/

As you will see, it is mostly about efficiency, high power handling and output. Using Hi-Fi drivers and speaker designs won't work, in a PA role hi-fi speakers would go up in a puff of smoke very quickly.

But as you rightly said, the highs from most PA speakers really scorch the ear. So is high fidelity PA really possible? I don't think so, but it is possible to improve on the average PA setup. First, move away from the usual diffraction horn and use a better sounding horn / waveguide with a good quality compression driver, like one of these:

The 18Sound XT1086 performs very well and is close to Hi-Fi IMO. It still uses what looks like moderate diffraction geometry in the throat, but it sounds much better that the usual diffraction horns, It is also inexpensive and widely available. Suitable for mating with a high end 12" pro midbass:

http://www.eighteensound.com/index.aspx?mainMenu=view_product&pid=178

It mates well with the following compression driver, which is one of the best Europe has to offer, some would say it is the best:

http://www.eighteensound.com/index.aspx?mainMenu=view_product&pid=266

Another horn to look at, is the DDS ENG 1-90 Pro. It is used in some well reviewed hi-fi speakers and members of this forum have experience of it. I have not used it, but I expect it to sound better than the XT1086:

http://www.ddshorns.com/catalog.php?page=ENG190Pro

But the best sounding horn / waveguide is probably the oblate spheroid by Earl Geddes.

See:

http://www.gedlee.com.

A lot of effort will be required before you have an OS waveguide in hand, but if you can convince Earl to sell you some 15" waveguides, you can combine those with a 15" pro midbass and you will have a good sounding PA monitor with high output. But I don't think the waveguides will be cheap.

[chasw98]

A big difference in the 'home' vs. 'pro' category is that in the pro world most speaker cabinets are designed to hold the drivers and any horns/waveguides that may accompany them. All crossover and amplifier gear is outside the box. So what you end up with is a very modular system where one night you might need 4 bass bins, 8 mid cabinets, and 4 horns........... vs. another night needing 2 bass bins and a mid and horn cabinet. Along with the speaker cabinet compliment you would also need to haul the low level and amplifier racks appropriate to the needs of the venue. Equalizers, crossovers, limiters, etc. and the power amps needed to run the rig.

As far as 'high fidelity' in a PA sound system, it is quite expensive to provide live sound for audiophiles! I used to run a full Meyer system that cost over $50,000.00 and that was for a one man band! But it sounded very, very good.

If you have some experience and choose your components wisely you can provide good sound at a reasonable cost, but the differences between PA systems and Home systems are very wide. You really need to have experience in pro gear to do it right economically or know someone in the business you can get help from.

Go here and do some poking around. http://srforums.prosoundweb.com/index.php/i/0/

Chuck

[Dennis H]

Here are a couple of sites with plans and/or kits for PA speakers. They aren't 'open source' like this forum but they do have their own forums. I can't comment on the sound.

http://www.pispeakers.com/Products.html

http://www.billfitzmaurice.com/

[augerpro]

How will these be used? I was assuming home use, which is where my idea and those projects at Bill F's site are sort of geared. If this is for live sound then as Chuck pointed out there may be other considerations. Do you have a link to those JBL's your B in L was looking at? They're probably actively powered and crossed?

[NateTTU]

I'm gone for a day and wow, this thread really took off. This will be for live sound, not so much home use, but I may have to point my brother in law over this way because he would be able to answer any and all questions much better than I.
I seriously doubt he would be into the idea of designing his own. I didn't realize that criteria was so far off what we normally have in this forum. I will try to find those JBLs, but they can't be that great for only $700 a pair.

Nate

[Dennis H]

I didn't realize that criteria was so far off what we normally have in this forum.

Well you want something with the SQ of the Statements, that will play much louder, and cost much less. See the problem?

[jeff_free69]

not sure how loud you really need it - I'm working on something good for moderate live levels, suitable for a typical bar.

http://techtalk.parts-express.com/showthread.php?t=207622

the problem I found is that most 10" and 12" get really nasty above 1K, so they aren't suitable for midrange a smooth sounding system. you'd probably have to go for a really expensive 2" horn to get down that low. I'm using 2 $40 eminence alpha 6's per cab which gives about 96 db efficiency and should handle 200W . On top is a selenium 210Ti driver in a wide disperion horn and on the bottom will be a 15" by the time it goes out the door. THey are extremely smooth, (i've been listening in my living room (where my Zaph SR71s are !)
I hope to have them trimmed up this weekend, then I'll post pictures

[supadave57]

Hey, I'm Nate's brother in law, just got set up at this website...

A year ago I wouldn't have even considered trying to build speakers for my band, but after hearing Nate's system... I love DIY projects, the price is right, and the quality is excellent.

To give a little intro on my band and my needs, we're a four piece alternative rock band, but also do many gigs leading worship in churches. We usually play for 50-100 people but have needed our own system for crowds of up to 700. We mic everything: vocals, amps, drums. I'd like everything to come through the system (rather than through individual amps) as it gives a much more unified sound. I'm looking at putting out between 120-130db when everything's turned up.

Budget-wise, getting the most for my money is of course nice, but I'm hoping to build two mains and two subwoofers for under $1500, not necessariliy counting the power amps or wires.

Quality-wise, I'm looking at getting something at least as good as the JBL MRX series. Here's a couple of links to the mains and the subs:

http://pro-audio.musiciansfriend.com/product/JBL-MRX512M-12-2Way-PAMonitor-Loudspeaker-Pair?sku=600416

http://pro-audio.musiciansfriend.com/product/JBL-MRX518S-Single-18-Subwoofer-Pair?sku=600417

They are $1300 for the mains and $1300 for the subs. The MRX series sound pretty good for what they're worth, and put out enough sound for what we're needing.

Something I've thought about is using 12" drivers for the mains, as this would help with the midrange, and the subs would cover the lows. I wouldn't ever be using the system without the subs. I've been looking at Parts Express at how to build the boxes (MDF, carpet, handles, etc), and think I have a pretty good grasp at that. However, as far as what drivers to choose, how to build the crossover, etc., I'm pretty much in the dark. I noticed alot of the drivers in the price range I was looking at were made by Selenium and Eminence. Has anyone had experience with these brands?

I hope this helps you guys understand a little about where I'm coming from- thanks for the help!

[Dennis H]

Welcome to HTGuide, Dave!

When you're looking around for a system to build, keep in mind that the crossover is a very important part (some would say the most important part). You can't just buy a prefab crossover and expect good results. You'd do best picking a complete design that has been worked out with a custom crossover and custom cabinet for the specific drivers rather than just picking some drivers that look good and trying to come up with a design from scratch. Nothing wrong with doing that as a hobby but there's a steep learning curve before you'll likely get anything that sounds decent.

The good news is you can start with one speaker and see if you like the sound. If you like it, build more to get the SPL you need. If not, you haven't wasted a ton of money and you may be able to reuse some of the parts in a different design.

Have fun!

[supadave57]

http://www.billfitzmaurice.com/ and Folded Horn Design

Thank you everyone for your posts and your help! I've been looking into the designs at http://www.billfitzmaurice.com/ (thanks Dennis for this link)

Bill uses a folded horn design for his speakers. Has anyone had good experiences with these types of speakers? His website makes his speakers sound almost too good to be true, where a $200 speaker is comparable to a $2000 commercial one. Does this sound about right? Is it about the same with HT speakers? Are folded horn speakers worth the trouble of building them? They seem complicated.

Also, while Bill's speakers have high spl ratings in the live sound range (the overall efficiency is rated at 106dB for the mains @ 1w/m, so 100w gives me 126dB, right?), this doesn't say anything about the sound quality. Besides having a pretty flat line in the spl frequency chart, what else should I be looking for? It appears these speakers can use different drivers, depending if I want to go cheap or expensive... both the mains and the subs use 10" drivers (the mains use tweeters as well), so does anyone have opinions on what are good 10" drivers, either for the mains or for the subs, on what they thing sounds good? I know alot of this is subjective, but I'd like to use good drivers that don't distort easily and have a very clear sound.

The big difference, from what I can tell, in live sound vs HT, is that HT needs good frequency response way down in the Hz, while live sound needs to get quite a bit louder, but only needs to go down to about 40Hz.

[ThomasW]

Something to consider. The pricing is right...

http://www.erseaudio.com/Products/SPXProSpeakerCabinets

[John_E_Janowitz]

Hi Dave,

A few things need to be considered with your design. You mention you mic everything, but what specifically are you playing? The low note on a bass guitar is going to be 30.87Hz, so if you want to play that cleanly takes a lot of output from the subwoofer. Larger kick drums will require more excursion as well. My friend has an old 26" kick drum which has a much lower tone than the one in the portable set. If you plan on a lot of electronic stuff like keyboard this will also require a lot of extra excursion. In general though, kick drum and snare are going to be the two most dynamic issues. You'll need a decent compressor/gate for these if you don't already have one. http://www.dbxpro.com/266XL/266XL.php The DBX is a good unit.

That said, I can give you some ideas. We've done quite a bit for a local company in terms of monitors for front of house and subwoofers lately. Most of the other systems used around here are JBL SRX, and one company has a turbosound setup. Many people here can attest to the quality of the Lambda woofers. Most regard them as the lowest distortion drivers available. For the live sound application their ability to quickly pull heat from the VC is critical as they have very low power compression.

I've done 3 systems now for Elite Audio and have cabinet plans I could get to you. The first is his large monitors for the big system. They use a pair of TD15M's with the BMS 1.4" coax compression driver on 18sound XT1464 horn. These are the tops used in all of the large shows. The horns have a 40x60 degree coverage pattern. They can be towed in for smaller venues to help avoid reflections off the outside walls. One of the common venues that has quite a few national acts has about 1200 people capacity. He uses these large tops along with the stack of 4 subwoofers per side. We constanty have front of house guys asking for our cards as they haven't heard a system like it. You can see these here in a picture and on top of the subwoofer stack.

http://www.aespeakers.com/phpbb2/viewtopic.php?f=3&t=1690

The pair of TD15's per side is seeing one channel of a Lab Gruppen PLM 10000Q with built in Dolby Lake processor. Meaning each driver is seeing as much as 1250W. At the mix position which is 50-60ft from the stage we see continuous levels upwards of 110dB and peaks of 120dB. Levels towards the front of the room are obviously much higher. The riders for most all national acts require 110dB at the mix position. What most people find about this system is that it can remain extremely clean at these levels. This is partly due to the TD15M's, partly due to the BMS compression driver, and partly due to having a well setup system to begin with. At these high levels, the extremely low power compression on the woofers begins to be a large factor.

For the small system, Elite had a single TD12M with a 1" BMS compression driver on the 18sound XT1086 horn. These were the tops he would bring with a pair of the 18" subwoofers when doing sound at smaller bars or clubs for up to 200 people or so. At shorter distances they are still capable of very high levels as you can expect 125dB and even higher at 1m. They have a little wider dispersion patten on the horn of 80x60 degrees. You can see those in the picture of the outdoor stage also. As the large monitors don't have an overly wide dispersion pattern, they are often aimed more for farther distances. The small monitors are then mounted on stands and turned inwards as center fills in the large system.

Eventually Elite then decided they wanted more output from the center fills so we redesigned them using a pair of the 12" woofers with the same compression driver and horn. As he had plenty of power available, this gives a full 6dB more output capability and gets output up well over 130dB at 1m distances. Upon getting these finished he then bought a second 4 channel 10,000W lab gruppen amp and put together a second full system.

Subs are 8cf cabinets tuned to 32hz with 10" diameter round ports. The original drivers are B&C TBX 100's. We are now prototyping the first of our TD18H woofers that will be replacing those for him. They will be tried out for the first time on his small system on newyears eve. I also just recently did a pair of subwoofers for my church. The sanctuary seats something like 300 people. Each subwoofer is a single TD15X in about 6 cubic feet. Each will reach mid 120's down to 28hz or so. I wanted them to go a little lower due to the style of worship. There is a lot of bass guitar, keyboard, etc.

What you are doing should be fairly easy to come up with something for. One thing you'll probably want to do is figure out an upgrade path for down the road vs spending everything at once. For around 50-100 people something like those small tops with single 12" and compression driver on the horn should do quite well. I'd strongly recommend buying either the Behringer DCX2496, or ideally a DBX driverack 260. This gives you 2 inputs and 6 outputs. You of course then need the amplifer channels to power everything, but it is well worth it. You'd need 6 amp channels total, plus whatever you need for monitors on stage. Although I'm not a big fan of them, EP2500's are cheap, so getting 3 of them isnt' a huge investment. Doing a passive xover for home theater type applications with low power isn't too difficult. When you start talking about pro audio speakers where you're looking at upwards of 1000W possibly it becomes much more of an issue. You need to closely look at the voltage on all components as levels are turned up to make sure you aren't going to burn anything up. The dcx2496/260 give you the ability to do your crossover, eq, compression, limiting, time alignment, etc all in one nice package. Elite's small system has one 260 to run the entire system. Each channel has it's EQ for setting up the speakers, then you have EQ on the inputs which you can use to EQ any room you are in. If you plan to be in a venue multiple times, save the program and you can recall it the next time. You set your limiting and compression so that you cannot clip the amplifiers. That way if someone happens to be mixing who isn't that familiar with the limits of the system, they can't damage it. We do this for club installs as DJ's always like to push the limits of a system.

Obviously my overall recommendation is for our drivers, but i think it may be best to follow an upgrade path vs spending more money at once if you don't need to. You can build the cabinets with the intent of putting in different drivers later if necessary and go with less inexpensive drivers to start. The 18sound XT1086 is $88 at loudspeakers plus. I'd recommend them as your horn. You can then go with any number of compression drivers from the Selenium D220 for about $45 up to the BMS, 18sound, B&C, etc upwards of $100. For what you are doing now I'd think the D220 would be fine, but if you start playing for larger crowds you'll want something that can handle higher levels and more power. For the 12" driver in this case I would still recommend our TD12M. As this driver will cover everything from maybe 75Hz on up to 1200-1800hz, depending on the compression driver used, this is a very critical driver. You'll be covering snare drum, vocals, guitar, etc. There are some other decent drivers out there, I just can't think of any that will save a significant amount of money over the TD12M that still sound good covering this entire range. You could use an Eminence Beta 12 on a real budget, but your power handling will be quite limited and you're going to run into distortion issues with the upper frequencies with low frequency excursion. Getting the TD12M also means I could get you all the settings you need for your tops for EQ, crossover, etc and you can just put them right into the processor. For subwoofers, our upcoming TD18H is really without equal, but not in your budget now. The Dayton PF460-8 could work well as a budget driver in the same cabinet and give you an easy option to upgrade later.

So 2 XT1086, 2 selenium D220, 2 TD12M, and 2 of the Dayton PF460-8 comes to about $1150 and gets you up and running. It also gives you the option later to add a better compression driver which can allow you to get another 6dB or so out of the tops and upgrade to a TD18H for the subs down the road allowing another 6-8dB more output from those cabinets. The dcx2496 or driverack 260 also allows you to make easy adjustments when you do the upgrades.

John

[looneybomber]

Hey John, I don't mean to get so off topic, but what's this about TD18H's? I'm enjoying my TD15H's as sub/midbass duty, and hope to finish my 3way's this summer. Are you intending to use the TD18H's as midbass/sub duty, or strictly sub? If only sub duty, why not build off the AV series?

[John_E_Janowitz]

Hey John, I don't mean to get so off topic, but what's this about TD18H's? I'm enjoying my TD15H's as sub/midbass duty, and hope to finish my 3way's this summer. Are you intending to use the TD18H's as midbass/sub duty, or strictly sub? If only sub duty, why not build off the AV series?

The TD18H is going to be using the 2.5" coil motor, similar to the AV, but it will be a solid pole with the phase plug as well. Full copper sleeve on the pole, so they will be very clean up to the point where we have cone issues. Up to 500hz wouldn't be a stretch at all. They could be very good for sub/midbass use in a massive 3way system. We have 14mm Xmax with 18-20mm physical suspension travel. I'm not aware of any pro 18's that are upwards of 11-12mm. Efficiency is around 97dB 1W which matches all the traditional drivers EV, JBL, B&C, etc. Due to the 4 layer copper coil though we have quite a bit of mass and Bl. Compared to the B&C 18 TBX100 you have quite a bit more output at tuning in a vented enclosure while keeping the same efficiency up higher.

One thing that is of great interest too is that with our VC design and the very thick 3/4" gap plate, we have anywhere from 2x-4x the area of the coil adjacent to the top plate/pole as most of the 3" and 4" coil pro 18" drivers! Between this larger heat sinking area and the copper on the pole pulling heat away much quicker, our 2.5" coil will exceed most of the 3" and 4" coil drivers for power handling and power compression. Then the phase plug is 2.5" diameter and about 4.5" long solid aluminum (around 2.5lbs) so you have a massive heatsink to pull heat from the pole too.

John