Is It A Good Idea To Build A Cab?

Discussion in 'Amps and Cabs [BG]' started by s7on3d, Sep 20, 2002.

  1. s7on3d


    Jun 26, 2002
    Ra'anana, Israel
    I'm thinking (in the long run) about buying a nice head (200 watts or so) and then building a cab to go with it. I know NOTHING about the subject of electronics or anthing else, but I have a friend who builds speakers for sound systems. What I want to know is weather or not it would be a good idea to build a cab with my friend, and if so, what speakers should I use, do the ones at Radio Shack sound good as an instrument speaker? Is there any guideline to go by when deciding on the measurements of a cab? Last but not least, what setup should I go for? 115? 210? with tweeter or without? (I love the bass roar of a nice 115, but i also love the punchyness of a 210. I play Jazz, Modern Rock and I Slap. I never use a pick)
  2. Tumbao


    Nov 10, 2001
    I'd like to build two 12"x 8" cabs, but this is not an easy job specially if you are a sound perfectionist
    without expertise in this area.
  3. s7on3d


    Jun 26, 2002
    Ra'anana, Israel
    I forgot to say thank you to everyone for the assistance.

    P.S.-I didn't bring up 112 or 212 configs, but they are options... as is anything else you think would be relevant

    Thanks again,
  4. Brad Johnson

    Brad Johnson Commercial User

    Mar 8, 2000
    Gaithersburg, Md
    Boom Bass Cabinets, DR strings
    Eminence would probably be the way to go for drivers. As far as cab configurations, I just hit on a combination I'm very happy with, a small 1-15 and a 12 with a horn. In the proper box, the 400w Eminence drivers work very well and don't cost a lot either. Very cost effective.
  5. geshel


    Oct 2, 2001
    The thing is, if you're going to go with an off-the-shelf driver and put it in a carpeted plywood box, you're probably better off (money-wise) buying one from Avatar or somebody (the Speakerhole ones look a little too iffy to me though).

    As for designing the cab, yes, there are "things to go by". It's not very simple - ask your friend who builds them (assuming he knows what he's doing). You can get standard designs matched to specific drivers from the companies that make them, like Eminence and EV. To design one from scratch though, you'll need to do a bit of studying and grab one of the little box-design programs available on the net (perfectbox, WinISD, etc). And, even then, generally you need to have low expectations for the first speaker or three that you design :). So, if you get plans or have somebody design the box for you, it might be worthwhile if you'll enjoy building it.
  6. Buy one instead.


    You'll be much happier with the sound, it will cost less, and you will get instant gratification. If/when you decide to trade up, you won't lose your butt on the deal.
  7. s7on3d


    Jun 26, 2002
    Ra'anana, Israel
    My friend builds his own speakers, and sells his home made speakers, but I wouldn't say he knows what he's doing........ He never learned from anyone, he just builds speakers with the trial and error theory. The reason i'm thinking about this is that I live in Isreal and buying a stack system here can cost MAJOR $$$ (about 3-4 times the price in the US). I was thinking that I could bring an amp from the US (forgetting to tell the customs officers that I have it ;) )and then I could build a nice cab... but if sounds like it will come out sounding like a dead goat. Should I just give up the idea (considering that me and my friend would probobly f*** it up), or try it? Either way, what speaker config would work best for my kind of playing?
  8. The reason to build a cab instead of buying one, is when you cannot get what you what from a commercial cabinet. This sounds like your position.

    How low does it have to go?

    The lower the response, the less efficient (loud) it will be, and the more amplifier power it will consume. If you play 4-strings only, it is a waste of money to build a cabinet capable of low B.

    How much size/weight you can tolerate?

    Hard experience will teach you that four 1x15 are easier to handle than one 4x15 cabinet. You can split them to either side of the stage, or only bring as many cabs as you need for a specific venue. The negative to multiple cabinets is a bit more materials expense and 4x the amount of labor to build them. The positive side is flexibility and smaller individual cabinets.

    How much noise do you have to make?

    It takes much more speakers and power to keep up with a 100w Marshall stack than it does to keep pace with a Peavey Classic 30. You can use the published SPL value of your speaker to determine how loud it will be. The DB tab in my spread sheet has a calculator where you can plug in SPL and see how loud it is with various power inputs and distances.

    What tone do you want?

    Flat response ("HiFi") cabs such as Acme use lower efficiency drivers in correctly sized cabinets. This extends the low end response but at a substantial loss of loudness.

    The Eden XLT drivers are much higher efficiency and have a pronounced boom around 80 Hz as a consequence of the drivers being in a cabinet that is too small for them to have flat response. However, this provides a significant amount of "cut through" in a live mix.

    The Carvin PS10 drivers are inexpensive but don't have any bottom. The JBL E-series are expensive, don't have any bottom either, but are loud as hell and very punchy. I'm building a JBL E155 now, and I fully understand it has no bottom end. But, it runs in a small 2.55 cubic feet (72 liters) cabinet and produces 100 SPL. It's perfect for a stage monitor where full PA support is available for the bass.

    How do I pick a driver?

    You can download my spread sheet, and sort it by driver size (inches), then sort it by ascending Fs (resonant frequency) order to find a starting point for the SBB4 vented alignments. I also have a number of other alignments worked out. Look for the color coded entries or sort on the "USE" column.
  9. patrickj


    Aug 13, 2001
    Baltimore, MD
    or.. you enjoy learning how to do new things, you've got the free time, interesting creative challenge, etc..

    Some people enjoy tackling difficult projects. IMO ;)
  10. Bingo. My personal cabs sound like nothing else, and that's a good thing. I've spent time to make em sound like that. Plus I wanted something a little lighter.
  11. All your questions will be answered by reading Geshel's reply. You need a box design program, and the makers specs for the speaker you are going to use, and you need to decide the shape of the response curve.
    Of course, you can just build any old box, and it will work, we are assuming you want the best results.
  12. If yopu decide to build then do it right. There are many things that can go wrong.
    1. get design that is proven. You don't have the resources for R&D.
    2. Don't skimp on drivers and hardware. Find the best.
    Use good materials and wood.
    3. Build it to last and take your time.
    4. reasearch first. Try different cabs to find what you like. open up some cabs to see how they are made.

    I built 2 cabs about 15 years ago from EV plans. I still use them for most of my gigs. I built a 115 loaded with a freshly reconed EV 15B and a 112 that now has a JBL e120. The hardest part was the grills and jack plates.
    I got to take some pics.
  13. Bigwan


    Feb 22, 2002
    Ballymena (hey)
    Hi Guys,

    Funny that this topic should appear again now! I've just ordered the drivers and hardware to build my cab.

    After much consideration I'm going down the 2x15" route.. although I haven't yet decided on whether I'm going to have them in one cabinet or 2! (I'm thinking 1 cab at the minute and bassing (ha-ha) my design loosely on the SWR Big Bertha).

    Good Luck!

  14. Suburban


    Jan 15, 2001
    lower mid Sweden
    Not because you'll do it right, and get a better cab.
    But because you will know more about cabs and sound afterwards.

    I think every bassist should make their own bass and cab (which are rather simple objects, that can be varied into the most elaborate complexity!), for that reason: to know what they are talking about.
    And, for calrification, I'm not talking assembly. I'm talking making from scratch every part that is within reach!:cool:
  15. FretNoMore

    FretNoMore * Cooking with GAS *

    Jan 25, 2002
    The frozen north
    If you know what you're doing, or take the time to learn how to do the calculations, if you buy top-of-the line components, and if you plan to keep the cabinet for a long time.... sure, build one.

    It will most likely not be cheaper than buying a brand name one though if you want similar performance. You may well be disappointed with the sound. The trade-in value is close to zero.

    I have built several cabs, they all sucked to be honest, it was a waste of money, but it was educational and fun! :)
  16. Bigwan


    Feb 22, 2002
    Ballymena (hey)
    I have to disagree on the cost of components and materials Vs. cost of equivalent cab...

    As I said in my earlier post I've based my cab on an SWR Big Bertha, which has a retail price of nearly £900 UK.

    My cabinet materials have so far totalled £250 UK with only the wood left to be purchased (and I'm not buying crap - for example I've ordered 2 eminence Kappa 15LF's which, although they aren't the absolute finest driver out their, they aren't too bad!)... sure if I was paying somebody else to build the cab for me it would be a lot more expensive, but I'm doing it myself.

    I think that's a pretty good reason for me to build my own cab on it's own ;)

    Whether my creation will perform in the same league as the SWR remains to be seen...:mad:
  17. You will do just fine with these two drivers.

    Put them into separate cabinets.

    The BB4 alignment will give you excellent (low) group delay numbers which translates into very "fast" and tight sounding bass. Eminence has justed started publishing the Xmech value, which is the maximum cone excursion. The 15LF will move 0.8" inches before damage, meaning it will take the full 400w input power without over excursing the cone. It will go beyond Xmax, and be subject to some distoration... but hey, it's a live bass cabinet.

    Link to Kappa 15LF Design Sheet

    The above Excel spreadsheet is worked out for the Kappa 15LF. To me, it is a fine driver for 4-string bass. The BB4 alignment is only 102 liters, making it easy to move. This is why I suggested doing a pair of 1x15. This driver is one of my favorites, since I no longer play 5-strings. It's tight, loud, and fairly compact.
  18. jpwinters

    jpwinters Guest

    Aug 22, 2002
    Norfolk, Va
    I built my own cab 2x10" 2x15". It sounds awesome. With my current set up it cuts through the band with no probs. 2 guitar players w/100 watt marshall full stacks, keyboard player, drummer with acoustic and electric kits.

    It all depends on how much you like to build things and how much research you put in to the project.

    My cab

    It doesn't lean, I just can't take a picture.
  19. Bigwan


    Feb 22, 2002
    Ballymena (hey)
    There's one thing I'd like to know jp...

    How's your back?
  20. Bigwan


    Feb 22, 2002
    Ballymena (hey)

    that spreadsheet is excellent (although I'm not sure I understand a lot of what it tells me)!

    I had thought of making the cab slightly larger... about 125 liters per driver.

    My problem is that I am an occasional 5 stringer (although it is occasional nowadays!)

    Would this be better for reproducing a low B?

    Transport isn't really a problem as my drummer usually gives me a hand with my gear (I can TBers fainting all over the world!!!), and I'm a big strapping lad anyway!