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Speaker size

yalcyalc Posts: 24
edited March 2007 in PA Connectivity
I rcently bought a DRPA and have been in the process of reconfiguring my P. A. system. This system is used mainly for a live rock & roll band in small and medium sized venues.
I run the system 3 way mono. My question is, Is there any rule of thumb concerning what size speakers to use for low, mid and high. There seems to be a wide variety of opinion on this matter so maybe its a personal preference thing, Especially on the mids.
Does anyone know? For low 18's or 15's dual or single, or some combination? For midrange 8\" 10\" 12\" 15\" or any combination? I've heard so many opinions on the midrange matter. For high end, Horns or tweeters? Someone said both- hmmm.
I'll greatly appreciate any info. Thanx in advance


  • DraDra Posts: 3,844
    Well, opinions are like noses, but some do smell better than others. I have heard (true or not) that it's 1 - 2 - 3. 1 horn - 2 mid's - 3 sub's. I don't adhere to that because I have a small system and don't do R&R shows.
    In a perfect world, go 5-way, 18's / 15's / 12's or 10's / 2\" horn's / tweet's.
    I personally prefer 12's for mid's (supposedly more natural in the vocal range and a smaller / lighter cab). But you have to run the subs a little higher.
    If you run 15's, then you'll probably cross lower and put more strain on the mid's amp, but your sub's will be sub's.
    It all comes down to what you want your system to do. Where is your emphasis?

    If you have access, set up a horn / 12 / 18 stack and a horn /15 / 18 stack. Preferably the top cabs should be the same line, ie JBL MPro 412 and 415 or Yorkville Elite E12and E15. Optomize each stack and compare. What sounds best is best.

    I word of warning. Most new DRPA users are disappointed by the sound until they learn how to use it. Read everything you can on the Former Forum link above. Speaker tuning, auto eq, crossover settings, sub delay, etc. Learn from other's mistakes before you make them yourself, or you probably will.

    \"That'll be 2 cents, please.\"
  • GadgetGadget Posts: 4,915
    Well Clay,
    As you have surmised there are a lot of things to consider when you are going to buy speakers.. The biggie is how you gonna pay for them..(read that how much money you gonna spend...GOT to spend) If the budget is large the choices are very exciting.. midrange they are also pretty good as we get lower on the denaro usable, the field starts to narrow quickly.

    I have kept a pretty close eye on the technologies and what is happening in this business and it seems to come down to this...

    Quality of sound ... the smaller the cone driver the better the clarity.. This seems to hold true for Mids,AND subs! Look at it this way. I was using 18\" EV S181's, and front loaded dual 18\" subs.... They are power hungry but they were fine... loud and good... I thought... then I built Labsubs that use 2, 12\" drivers...BOOM HUGE different whole different sound...these go lower, have FAR less distortion are more efficient, and they just sound luscious...I can't even listen (critically) to 15\" or 18\" front loaded subs any more... the distortion drives me crazy...Why is this? well if you consider the physics of it this is how it all pans out....consider that the 12\" and the 18\" speakers have the same magnet structure (motor) but the 18\" has the mass of a dump truck, and the 12\" has the mass of a Ferrari... which is gonna start and stop faster? Isn't that what a speaker does? The fact is the motor has to start accelerate.. slow... stop restart in reverse accelerate and so on many many times a second... mass is a constant, so is force, so we need to do all these things and the greater the mass, the more difficult it is to get started and stopped... Now why is the distortion lower in a Horn loaded sub? consider that ALL the sound needs to get out of the sub...in the front loaded design you hear every nuance.. so the frequency response of the speaker is tied to the frequency response of the driver.. in this case an 18\" cone driver. In a Horn loaded sub, the frequency response is LIMITED to the horn design. The design allows it to go so low, and by its nature it limits the High frequencies in that they get lost in the labyrinth that is the folded horn. The horn has other benefit/trade offs...The increased efficiency of the horn design, the naturally limited frequency response, and the large size are the hallmarks. Some people are used to the distortion of the front loaded 15 and 18 inch subs and think it translates into a low growl/punch...I happen to feel that that is simply education(or a lack there of) and as such once you find out what real low end is, you never go back...I know I can't.

    In midranges, there we also have a clearly defined very fuzzy line... Hmmm well its true. It is somewhat accepted within the pro audio community (that means it is less than a universal truth, but well thought of in its concept) that 12\" is the preferred midrange 10 \" is also well accepted, but once again there are trade offs...You see subs, especially the horn loaded ones, are limited by how high they can go frequency wise, AND more important subs start to sound HONKY when they get much over 120-150 hz... By comparrison 10\" and 12\" front loaded speakers used as midrange drivers, traditionally have limits of how low they can be expected to go. So now if we have to go higher than 120 hz to cross we are trading off the benefits we have achieved.. So what is the answer? usually you'll see multiples of those drivers and creative cabinet designs to optimize the low frequency response. Tthere are a lot of manufacturers that would have you believe that theirs is the only way...lets take it further now and look at the higher frequencies...

    Here the rub has often been the trade off of efficiency, projection, and sound quality. Speaker manufacturers have long been attempting to make horn loaded systems sound like studio monitors. Those monitors have dome tweeters typically, or ribbon drivers, and are by nature far smoother, and more open and more non directional in nature, meaning we cannot pinpoint the sound source so easily. The rub here is that with that type of dispersion there isn't great projection.. meaning the sound diffuses quickly. So what are the answers? EAW thinks they have solved that aspect with horn resonances.. I Haven't heard them yet, but I understand they are very nice, The Yorkville Unity series speakers have Mikey Kovach's nod and thats a DARN good endorsement in my book.. they are predicated on the unity horn, where the mids (3 cone midranges) and the driver are in the same aperture. Now the designer of this unity series is Tom Danley... Danley Sound. If you can afford his speakers, you would be the bully on the block! His unity horns have ALL the components in them.. woofers, mids and tweeters, and with the horn technology you get efficiency, pattern control, and unrivaled realism in sound recreation. and his low end... insane...He was the brains behind all the SPL labs designs as well, the Bass Tech 7's and BTW the designer of the Labsubs I spoke of earlier...

    Whatever the technology, its the end results that are the key here. The one universal truth I have found is that if you have a quality design, that is CAPABLE of doing what you expect of it (that means don't expect 2 studio monitors to cover 125,000 screaming Metallica fans.. chuckle) its the Sound Tech that makes the difference... I have gone into places where the system was BANAL... sounded horrible...I was asked if something could be done and with a good days work was able to identify the problems, make some changes, polarize, align and aim the system and tune it properly within the limitations of the design, and get quite stunning results. I have also gone to concerts, like the Bob Dylan concert at the XL energy center last fall, where all the technology and best equipment couldn't overcome the operator.. simply a terrible utilization of an L Acoustic line array system. I suspect that the artist, Bob Dylan himself had his hands in this somehow.. but I can only speculate... but the sound was awful....no matter where I went... and the Wings behind the stage... terrible..Well suffice it to say that any sound person can ruin a perfectly good system.

    So I think you should go out and hear some speakers, REMEMBERING THAT ALMOST ALL MANUFACTURERS LIE THROUGH THEIR TEETH TO SELL PRODUCT, Do your own tests...if your anal...case in point, JBL (and I'm not a big fan...) they have out the new SRX series... they rate the 722,725 @ 20K +/- 3 db... that should read +/- 20 db or more... The truth is, they can't get much over 12K...verified with SMAART and even with (JBL supplied) brand new drivers (there were UNMATCHED drivers on the shipped models...unbelievable) they still could NOT hit 12 k...?????

    One other consideration here is application. What the speakers will be expected to do...Line arrays are all the rage now but truthfully they are NOT ideal in all situations. The concepts however are. How many people will the system be expected to cover, what is the needed coverage...How long is the projected throw of the speakers.. how much is the room going to be a player in the sound? All these factors will need to figure into your purchase and if your not getting the answers you need find someone who does.

    Get a budget firmly in mind and go out an listen to some speakers... don't let the salesman have full control, turn some knobs... ask for a Peavey mixer or a Mackie to be hooked up instead of the Midas they are using to drive them... Try the same amps you have...see if they have something that you can take out and try...even if you have to rent them...make sure they are using the same ancillary gear you are in the chain. Make an informed judgment, do your homework, and you'll end up with a system that will serve you for years to come.
  • DraDra Posts: 3,844
    Just to prove a point about the former forum... except for a few ifs, ands, and buts, all of the info you just got, including the Ferrari story that Gadget tells is in there. After all, he wrote it.
    Keep up the good work G.

    Clay, keep us updated on what you do and how it goes.

  • yalcyalc Posts: 24
    Thank you,
    Lots to ponder Gadget. I will have more questions and comments-kinda busy right now. I have this weekend off to study this and experement with what I already have.
    Once again, Good job Gadget.

  • yalcyalc Posts: 24
    Hey Gadget,

    I have a couple more questions, Here's some background.
    I've been a working musician for about 25 yrs mostly as a consistent hobby ( Day job , wife, kids ect) During that time I have amassed alot of gear, Alot of which is collecting dust. Seems I could start a music store. I'd like to give you a list of the cabs I have on hand. I'd like your opinion.
    I'm not against buying new cabs but I'd like to use some of what I already have if possible. Maybe build some as well.
    2 Yamaha SW118IV
    2 EV single 15\" folded eliminator loaded with 800 w rms Cerwin vega drivers.
    2 Audio Centron ACE subs (dual 15)
    2 Yamaha S115v 2 way
    2 altec (huge) horns
    2 10\" midrange cabs that look horn loaded but there are no ports. They are shaped kind of like a horn. Only the voice coil portion of the speaker is exposed at the back of the throat. Someone told me they are made by \"Clark\" I can find no record of a company by that name.

    2 Yamaha 6115-1 compression tweeters. They are old but they sound great. Loaded with JA4281B drivers, they are huge and heavy. Quite something in their day I would guess.
    Do you see anything worth using?

    Next question, You mentioned both horn loaded and folded horn subs, Which do you prefer? Are there free plans on the web?
    Finally, What exactly is a labsub?
    Thanks for all your help. DBX support is the best I have encountered. I have called the company twice and was treated very well. This alone will secure me as a customer forever, Not to mention the quality of the product.
  • GadgetGadget Posts: 4,915
    AH yes I was working on this the other evening and the damn computer ate it...Do you have any pics of some of this stuff? It might help..
    As for the gear the Yamaha stuff is ok.. kinda DJ grade but...Don't know much about audio centron but the stuff I've seen I wasn't all that impressed with.. but DJ grade again..But at 124 db max and 400 watts it sounds like 2 1/2 \"voice coils... The EV stuff is ok...but I hate to see odd drivers that the cabs weren't designed around...The Altec horns are called cell horns and are pretty much used only for long throw applications... you might get smaller horns and use the drivers though. The \"Clark\" sounds like \"W\" bins an outdated design at best...

    Interesting.. those Yamaha horns are only 20 watts though?

    As for horn loaded and folded horn subs they are essentally the same technology its just that the horn on a folded horn is long and so its folded like a conk shell like spiral to help limit the size somewhat. Community is a manufacturer that used a lot of horn loading...

    I love the Labsubs...here is the plans...
    designed by Tom Danley, and comparable to the EAW 949supersubs that cost about 5000-7000 dollars... EACH...

  • yalcyalc Posts: 24
    Hey gadget,
    Your answer is pretty much what I expected. I'm sure you are correct about the \"w\" mid cabs. I have'nt seen them in years.
    I did notice on the Yamaha tweeters the cabinet says 75watts but inside on the driver it says 20w, However I like the sound of them and they seem plenty loud enough.
    Anyway it seems that my trying different combination of this stuff is as futile as rearranging deck chairs on the titanic...pointless. I could buy all the cabinets I want but I would probably just lose them in divorce court so I'm back to my original solution which is to build them. I have good connections for the baltic birch.
    If you would recommend a good design for mids and highs then I should be all set. I have built subs and mirange cabs in the past with very good results but never horns.
    You've been very helpful and I thank you for your assistance.
  • GadgetGadget Posts: 4,915
    Clay. Sell the crap.. build the labs... they are big and heavy but man they go low....the module is difficult to build and if your not a woodworker you might want to see if you can get a cabinet shop to do the cutting? oh well.. be for warned it took my more than 8 hours each...

    Here are some sites...
    These are primarily horn loaded projects...
    http://www.fane-acoustics.com/public_ht ... ure_15.pdf
    http://www.fane-acoustics.com/public_ht ... ure_12.pdf
    That should get you started...
    There's more of course.. I have some designs...
    but see what you think.
  • yalcyalc Posts: 24
    Thanks a bunch for all the info G. It will keep me busy and out of your hair for quite a while. I have no problem building any cabs. All I've built in the past have turned out perfect and I always end up selling them. I'm pretty handy with that sort of thing.
    I do have one more question, Is there a specific driver that YOU personally recommend for the labsubs? Forgive me if you already mentioned that, I did'nt see it. Those custom Eminence are awsome.
    I will post some pics when I get some cabs built.
    Thanks again
  • GadgetGadget Posts: 4,915
    The Cabinet was designed around that specific driver the LAB 12...use only that driver...

    Contact Loudspeakers Plus @ 847-963-0725

    Tell Jay I sent you please

    That Fane Site also has a killer design for small portable subs that kick ASS. when I use my proprietary 12\" two way's I use the 15\" as lo mids and as stand alone subs for disco/karaoke...

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