1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  
    TalkBass.com has been uniting the low end since 1998.  Join us! :)

New cab build with Eminence CB15-8

Discussion in 'Amps and Cabs [BG]' started by RodK, Nov 26, 2012.

  1. I am looking to build a more portable cabinet for my son . He has 2 peavey 410tvx's but wants something more portable for smaller venues.He uses a Peavey Nitrobass head and a Fender Deluxe Jazz 5 string.

    I can get an Eminence Legend CB15-8 locally. would this be ok on it's own or does it need a mid? Also when I model it in winisd, I am exceeding xmax (6mm) from 55 to 90 hz in a 4 cu ft box tuned to 40 hz. how can I fix that. If it needs a mid, is the Eminence Alpha 8mra good to use? I can't figure out how to model the alpha to see what it adds. If I need the mid, do I have to use a crossover?

    Any help would be greatly appreciated.
  2. If you go with the mid driver you will definitely need a crossover.
  3. it was -6db at 6 kh with just the 15, is the mid necessary?
  4. You'd be the coolest Dad ever if you built him a 12/6 cube fEarful.

    Plus, you get all your questions answered, plans accurate to the nth degree, and one stop shopping at Speaker Hardware. You can even get a precut, pre biscuited, flat pack, for easy assembly.


    This will get you to the plans.

    Here's Leland's site: http://www.speakerhardware.com/

    For a super simple 1-15, look at the TL-606 plans, and do a little figuring for the best driver. The driver you mentioned weighs 20 lb. For a big weight reduction, look into the neo drivers. With a Eminence 3015 neo (about 8 lb and better specs) the TL-606 can be pretty light.

    But, if you are going to spring for light weight neo drivers, you might as well go whole hog and build one of the fEarfuls with either the 3012LF or the 3015LF.

    I've built three fEarfuls myself, and the 12/6 cube with the less expensive alpha 6A mid range gets all the work. Currently, that particular cab is in such demand that it's doing more gigs than me. Everybody who borrows it is blown away and wants one. Huge bang for the buck, especially if you are able to build a simple box and can do all the work yourself. Mine came in right at $300 for parts and materials.

    One fun project, and it'll turn heads wherever it goes. The 4-10's will be gathering dust or get sold to fund the next fEarful build.


    Here it is, just before I buttoned it up by bolting the 3012LF in. That's all there is to it!
  5. The driver I mentioned is 17.3 lbs , neo's are out of my price range. His 410 tvx weighs 96 lbs, so this will be plenty lighter even with the Legend CB15-8.
  6. CL400Peavey

    CL400Peavey Supporting Member

    Nov 7, 2011
    Grand Rapids Michigan
    The concern I have with the Legend, is that it takes a hefty dive in response around 2.2kHz. For that to work for my tonal goals I would want a mid driver and that would require a cross over. The cost of those additions would make a Faital Pro 15PR400 conceivable. Get a 4 Ohm driver, and dump it in to a TL-606 clone scaled to work with 1/2" baltic birch. Take a good look at greenboy's bracing scheme and you would have a killer cab in both tone and portability. I dont recommend that particular driver because of weight, but because a single Faital will be ~4db louder with your son's amp than a legend, and sound much better doing it.
    PawleeP likes this.
  7. I built a 4.0cuft (int.) cabinet with just a single Legend CB158. Tuned to about 35hz. 1/2in ply all-around. Herculiner covering. It works just fine, as is. I've not thought that it needed anything else. I haven't done an official weigh-in, but it weighs more than 35lbs and less than 45lbs. I can lift and carry with one hand. I can't comment about exceeding xmax. I did not see that result when I was checking things in WinISD. I have not really pushed the cab too hard, yet. I use an Ampeg PF350 with the cab. Sounds good to me! (edit) My tonal goals don't include 2.2kHz. No poppin'... no slappin'... no chickin' pickin'... just BOOM!
  8. cl400peavey - If you are using the Legend CB15 t/s parameters that are in winisd they are different than the speaker that is now available.

    With the t/s specs from Eminence for the CB15-8 it had much better response. It modelled -6db @ 6khz.
  9. Passinwind

    Passinwind I Know Nothing Supporting Member Commercial User

    Dec 3, 2003
    Columbia River Gorge, WA.
    Owner/Designer &Toaster Tech Passinwind Electronics
    I was just about to post in your thread on another forum.

    WinISD is useless for predicting frequency response beyond a few hundred Hz. Look at the manufacturer's frequency response chart, note the testing conditions, and maybe plug the FRC into one of the speaker modeling apps that can make sense of things in your particular scenario. Boxsim or Akabak can both do that, for starters.
  10. will33


    May 22, 2006
    The Legend will play fine without a mid. It's just a little on the warmer side of the tone spectrum...not "bright".

    You could still shrink the box a little without losing any real meaningful lows.

    Could leave room in the build design for a later 6" add-on if you find you're really missing the 3-6khz area, or need better dispersion for standing up close to the cab in small stages.
  11. I will lok into those programs when I get home from work. I thought winisd was the standard program most people used.
  12. Passinwind

    Passinwind I Know Nothing Supporting Member Commercial User

    Dec 3, 2003
    Columbia River Gorge, WA.
    Owner/Designer &Toaster Tech Passinwind Electronics
    Boxsim is much easier to learn than Akabak. There is an English version, I'll see if I can find a link for you.

    WinISD is great for box sizing and tuning, but it doesn't attempt to model things like baffle step and non-pistonic behavior, both of which may matter a lot in fullrange bass cabs. But frankly, I'd just rely on feedback from TB users of that driver for a one-off build, plus do the homework in WinISD as you are to find any 'gotchas' with your chosen tuning.
  13. That's why I am here. Any and all help is appreciated. I changed the thread title to include the driver.
  14. will33


    May 22, 2006
    WinISD is good for the driver/box/port tuning relationship, which ends somewhere 200-400hz-ish. Consult the driver datasheet for what happens above that.

    That Legend, in somewhere 3-4cu.ft. at some common tuning between 40 and 50hz provides around 200 watts input before exceeding xmax. That may not sound like much...but it's really quite good. You would need another 200 watts, to equal 400 to get any really noticable difference in output, which few drivers can do, and of them, very damn few are suitable for a one-driver/fullrange use cab.

    Play with box size and tuning to get your desired balance of lowend flavor and powerhandling capabilities...let the top end do what it does.
  15. I've never got winISD to run properly on my computer, but I think you would raise the tuning a little to get 80hz playing loud.

    Almost no bass cabs can take full power at 50hz, most struggle with 60hz and some don't even get going properly at 80hz. Fundamental reproduction is the big fat lie of bass.

    Don't boost lows on the amp. Cut low lows, boost low mids for more "bass".
  16. Yes. What he said. Now I understand the earlier xmax comment. My box, tuned about 35hz, has max power of about 104watts around a 60hz signal. Power goes up either side of that. What does that mean? Well, it means that it shakes a lot of stuff on stage. It means the low D notes I drop down to are heard clearly. It means that my PF350 is at about 80% on the gain and about 80% on the volume, and the cab is still not distorting. It means that my bass mixes in nicely with 2 "tasteful" guitar players, a keyboard player and a "controlled" drummer. If I were playing in an uncontrolled band, I would want more, certainly. Now, when I put full range music through the cab, the higher freqs are weak. Sounds AM radio-ish. I expected that. But, all of the bass is nice and clear. That's what I want. Old school bass sound. Loud enough for a band. Don't need to split ear drums. The CB158 delivers.
    b-b-b-bass likes this.
  17. would the Alpha 8mra even add much?
  18. will33


    May 22, 2006
    It'll add a whole lot from 2-4khz. That's a loud driver. The la6cbmr might balance a little better.

    nick98338 is right about what you can expect from the Legend at a lower tuning. Raising the port tuning into the 40's may increase powerhandling some.

    The xmax limited numbers always look small, but consider, that's based on a sinewave input, which a bass signal is not. There is a transient peak for a few milliseconds when you first strike the note, followed by much less power demamd as the note rings out. So....a large amp turned up seemingly loud, still isn't putting out all that power all the time. It sorta comes in fits and starts as you play.
  19. Blues Bass 2

    Blues Bass 2 Supporting Member

    Oct 3, 2001
    Davenport Iowa
    Here is a link to a thread where I built a small light cab for the CB158 using Eminence plans .
    I put a horn in mine to make it full range but it doesn't really need it . You can use my cab dimentions and port length and leave out the horn , the cab will still be tuned close enough . If you port it in the back you will have enough room to add a mid if you think you need it , the LA6CBMR might be a good match like will33 says .
  20. This driver is a sealed back design, so a sub-chamber is not required.
    The non-horn loaded performance is +/- 3dB from 400 to 4000 Hz.

    This driver responds very nicely to horn loading.
    In a properly designed hyperbolic horn, you can get kickin' flat response from 500 to 4000 Hz.
    Within its xmax limits, you can expect 121 SPL at 31 volts.

    Eminence offers a 500 Hz passive crossover, with an 18dB/octave slope that works well with this driver.
    The downside is the woofer operating up to 500 Hz.
    This might sound boxy, and the woofer is somewhat directional at 500 Hz.