Building bass cabinet

Discussion in 'Amps and Cabs [BG]' started by Moma Jones, Aug 15, 2003.

  1. I want to build a 215 using a JBL E140-8 and a peavey balck widow 1502-8
    Both are eight ohm speakers in order to make a four ohm cab
    What dimenensions ports ect. should I have for a cab that can handle a five string active bass.
    I am crossing it over as a sub (under 100 hz) and running a mesa powerhouse 1000 full range
    Or should I run the two cabs full range together?
    Any help is greatly appreciated
  2. arose11


    Sep 30, 2002
    Kalamazoo, MI
  3. Thank you so much
    Other opinions are still apreciated
  4. K-Frog


    Feb 6, 2002
    Camden, AR, USA
    because as an older fart, my first thought would be to build a pair of matching 115 cabinets. easier to carry, smaller venues might require only taking one. Less to lug.

    i dumped my 410 in favor of a 112 + 115 stack, 70lbs total in two boxes.

  5. Split the cabs. You never mix two different model drivers in the same acoustic space.

    The BW wants 3 cubic feet, and the JBL requires 1.0 cubic foot. Tuning frequencies are different, also.
  6. MJ5150

    MJ5150 Terrific Twister

    Apr 12, 2001
    Lacey, WA
    bgavin has it right!

    I bought a Yamaha 215 cab. After about a week one of the 15's blew. I went to the music store, and bought a new Black Widow 15, and threw it in.

    I do not understand air movement, and speaker dynamics, but I DO know what sounds like crap. My cab did. It had something to do with the throw on the 15, and phasing. The BW was superior to the Yamaha and the two were not "playing nice". The result? I went right back to the store, bought another new BW and now it is sweet. Now I have this cab, and two Yamaha 15's, I had the bad one repaired. It had to be reconed.

    Either use two of the exact same speaker, or try the two 115 suggestion.

  7. I would still like some more input if possible:confused: :confused: :confused:
  8. rdkill


    Jan 20, 2003
    If yur waitin' for someone to say it's OK to put two mismatched drivers in the same cab - well why did you bother askin' if you're not gonna listen to good advice? :rolleyes:
  9. aladdin


    Mar 7, 2003
    Chiba, Japan
    Hey guys.

    These guys are for the most part giving you good advice my friend. You should not put two different drivers in THE SAME space. That does not mean that you cannot put the two drivers in the same cabinet though.

    If you do this, you need to create two chambers in the cabinet. That is, effectively two boxes in one. Each driver's efficiency concerns, space allowances, volume requirements, porting, etc is decided and taken care of separately. However, this can be difficult to build and inconvenient. The box also has to follow the dimmensions of the largest driver concern.

    The easiest way to go is to use two identical or near identical drivers. If you want to use the two different drivers, you should isolate them from each other. In this case, what K-Frog says is best. Build two cabinets. They will have different sonic signatures. You could choose one or the other or both. If you go through the trouble of building a driver-specific cabinet with dual chambers and then decide you hate one of the drivers, you cannot replace it with the one you like because the chamber is the wrong dimensions.

    I have built such a cabinet before. It was a 2and 1/2 way design 2x10. It contained one 10 inch that was very efficient and had excellent mid-range and treble response. The other 10 was less efficent but flat to 30 Hz in this cabinet.
    The crossover allows both drivers to play the bass range but only the 1st 10 is allowed mid-high frequencies. The second, less efficient 10 is cut off at 800 hz (18dB/o). This is, in effect, a 1x10 with a sub! The boost is where it is needed.

    If you are going to do such a thing, it helps sonically if the two drivers are made of the same material also. In my case they were both stiffened paper cones.

    good luck.

  10. Ok thanks I`m going to build two cabinets
    I just want ted the LOOK of one cabinet but sound is WAY more important
    Thanks to everyone who took the time to further my education

  11. Well, if you're clever you could probably design the cabs to 'look' like one, and then you'd have the advantage of two easier to carry cabs instead of a refrigerator. heheheh

  12. Rockbobmel

    Rockbobmel Supporting Member

    Just for the yuck of it, I Ran my Mesa 400+ into my P-1000 cab and my 4-10 Eden& 1-18 Sonic on the other side. The power got split and the fact that I was running 2 ohms,it was not any louder, just spread out..... My point is, If you think you will get any monster gains, you won't unless you add another amp. If however you want more solid bottom fom your Mesa, try replacing/reconing with the 15B driver. I replaced my 15L withan Eminence Kappa Pro 15, BUT, my cab is modded to seal off the 2 210 compartments. Do a search nd read my Frankenboogie thread.
  13. Petebass


    Dec 22, 2002
    QLD Australia
    I curious, what made you go for such an unusual combination drivers? I'm not picking on you - actually I like to see people trying something different.
  14. I bought a used cabinet with the black widow in it, but the cab was built for the JBL driver.
    The former owner said he changed it cause he want something for volume and not just sound.
    He said he runs his stuff HARD so the JBL wouldn`t handle his head (The peavey firebass I now also own)and ended blowing the black widow any way but thankfully they have field replaceable baskets.
    So I bought the cab with blown speaker bought JBL to put in it and replaced the cone on the Black widow
    I do want to experiment
    I have a wicked cab now (MESA powerhouse 1000)
    So im not relying on this cab to work
    Just want to make mistakes so I can learn about building cabinets
    And to "bgavin" thanks for the sizes
    could you elaborate about tuning freq

    Any other help or suggestions or "your a stupid guy" is really appreciated
  15. Download my spread sheet and look at the DRIVERS tab. Find the driver you are interested in, and it has all the cabinet volumes and tuning frequencies for the various popular vented alignments.

    I have worked out the frequency response in SPL at 32, 43, and 89 Hz as a generic indication of how the driver performs in the low register. These SPL numbers take into account maximum acoustic power limited by Xmax and/or thermal limitations of the voice coil.