Making your own cab.

Discussion in 'Amps and Cabs [BG]' started by Zoot, Jul 11, 2005.

  1. Zoot


    Sep 4, 2004
    I have a SWR Super RedHead. Fantasic 2x10 combo, but just not loud I would like to add an expansion cab. (Undecided wether a 2x10 or 4x10)

    As 4x10 retail in the UK for approx £800 ($1400) its too expensive for me. However, I could buy 4 eminence speakers for £150 and MAKE one myself.

    Does this sound feasable, or is it a waste of time and will sound rubbish?? (I have basic woodworking skills so making it swould not be a problem, but I know nothing about sound/dimentions/ohms etc..etc.. )

    Any advice would be great.
  2. Rat


    Mar 15, 2005
    Boston Sewers
    there are a tone of treads on this subject...hehe I asked too

    do a search for DIY cabs, I would go with a 15" speaker under that 210..should be cheaper too :D
  3. Groundloop


    Jun 21, 2005
    If you're using a PC, you should be able to Google a ton of of freeware cabinet calculators. There's not so many for Mac, but I found this one. Plug in the Thiele-Small values for the drivers you want to use to give you the dimensions for the box. A side note, this calculator spits out box dimensions that conform to the Golden Ratio, where H=1.67, W=1, D=.67 (give or take a few hundreths). You can adjust these dimensions to get a more 'traditional' looking cabinet. Compare the dimensions of cabinets from Eden, SWR, Ampeg etc. The important factors are the volume of the box, and the port size.

    Good luck.
  4. Zoot


    Sep 4, 2004
    I have done a search, but there seems to be SO much dissagreement and misunderstanding on the whole thing?!!?

    You'd think that there would be a basic blue print layout somewhere here.
    A fact sheet that tells you exactly how to build a 4x10 or 2x10 using the more common Eminence speakers etc.....

    It seems that most Bassists on here want either a 4x10 or 2x10 usually powered by Eminece drivers.
    Someone should write a DEFINITIVE guide of how to build giving exact dimensions etc

    Still....easy for me to say....maybe I should be less lazy and try and get my head around the whole thing :(
  5. I used WinISD that worked out pretty well, except for the ports, but I think I was reading it wrong. Some folks here were pretty helpful esp BillFM.

    Do a few calculations before you decide on what drivers to get - I went with bp102's which sound great but aren't that loud, and need a pretty large cabinet as they move a ****load of air.
  6. Download WinISD from and put in the driver's Ts parameters to find out how much airspace your speakers need. Then click the box shape button and put in the depth and width of your SWR cab (so they stack,) and click the H to calculate how high the cab needs to be.
    I have a 2x10 combo that I put Eminence deltalite 2510 drivers in and it sounds really great so I recommend those. They have 2.5 cu ft of air total and the cab is tuned to 41hz.
  7. Bigwan


    Feb 22, 2002
    Ballymena (hey)
    DeadRBassistNJ what volume levels are you pushing your deltalites to? I've been considering replacing the driver in my ashdown 1x10" combo with one of those...

    Zoot - as a beginner project put an eminence kappa 15LF into a 3.62ft enclosure. I built 2 of these a few years back and they are very good for adding bass extension and volume. As standalone cabs they'd be fine if you're into the "no upper-mid and treble" sort of sound but wouldn't hold up in the upper end of the spectrum for slap, etc. One of these underneath your super redhead should help your volume problems! As standalone cabs, other than being shy in the upper range they are far better sounding than the older SWR 1x15" offering (the "basic") which I once owned.

    I can't remember the dimensions of the port on my cabs but there are plenty of equations for that about the web. To save Bgavin posting here, go to and download the musician's reference file. Go the the drivers page and you'll have all the info you require for almost every useable driver on the planet...
  8. I'm pretty much cranking it. When I use the head in the combo the volume is at 3 oclock with the gain at 12oclock, and when I use my firebass head with it, it really wakes up and puts out 2-3x more volume at 12oclock and 12oclock. They're holding up fine and dont distort like the stock ones did. They have nice low end at recording volumes and they cut through at higher volumes. I recorded with that combo and it sounded pretty similar to the studio engineer's EV 2x12 monitors. The recording can be heard in that Nevr Deadr Society link below.
  9. ESP-LTD


    Sep 9, 2001
    Not at all; there are just alot of choices. It's like 'what is the best car'- there is no 'best' only 'best for a specific set of circumstances'. And unfortunately, it does take a bit of study to understand the lexicon and what all the trade-offs are.

    Decide what is most important: size, low end, or loudness, and then build the design that maximizes what you desire. No, it's not simple; but 'simple'; doesn't always sound the way you want.
  10. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    Why not just go to a speaker building website? There are at least four. Another option is to ask Eminence.
  11. 1/2 cup butter
    1 cup white sugar
    2 eggs
    1 teaspoon vanilla extract
    1/3 cup unsweetened cocoa powder
    1/2 cup all-purpose flour
    1/4 teaspoon salt
    1/4 teaspoon baking powder

    3 tablespoons butter, softened
    3 tablespoons unsweetened cocoa powder
    1 tablespoon honey
    1 teaspoon vanilla extract
    1 cup confectioners' sugar


    Preheat oven to 350 degrees F.
    Shape mixture into the form of a bass cab.
    Bake in large oven for 72 hours. (cab will firm up upon cooling)
    Serves up to 400 watts.
  12. Antonius


    Nov 26, 2002
    And now for something completely different :smug: Some not too expensive but pretty impressive cabinets can be built using Bill Fitzmaurice's horn loaded designs:

    If all you need is some extra bottom end, a Tuba 24 seems a good fit (single 10" sub, Eminence Beta 10 or HL10a, eats any regular 4x10" bass cab for breakfast as far as low end is concerned).

    For a full range bass cab, look at either Omni 12 or DR250 (more than basic woodworking skills and some patience recommended for the latter, but those who built one all agree the result is well worth the effort).

    BTW - I haven't built nor heard any of these so cannot tell from experience yet, but have been reading about them for a while and plan on building both a T24 and DR250 when I have more time.
  13. Eric Moesle

    Eric Moesle Supporting Member

    Sep 21, 2001
    Columbus OH
    Building a cabinet to SAVE MONEY is usually a bad idea if its your first attempt. The results are usually bad, and you learn a bunch in the process that you can correct later. Besides, major manufacturers get their parts super cheap in bulk, which one-off attempters cannot match. Many people learn the hard way that building your own cab often costs much, much more than you can find a quality used cab for, and the results are nowhere near as good.

    The best reason to build your own cab is to learn, and to make something that isn't offered in stores, something you cannot find elsewhere.
  14. Funkengrooven

    Funkengrooven Turn it down? You gotta be nuts!!

    I agree with DeadRBassistNJ and download winISD...
    That is a very good package.
    and again. decide what you need.
    Volume at any size?
    Low end at any size?
    Best volume at a small size?
    Best low end at a small size?
    Best compromise of all?
    If you watch the graph in WinISD it will show you where the frequencies will be prominent with which design.
    and reverse engineering someones else's is a good idea too.
    I have used WinISD many times and it gives good results,
    just take your time and explore all the possibilities before you put saw to wood.

    and emminence is definately a favourite driver...I personnally prefer JBL as do a bunch of JBL bigots around here.

    although JBL's out of the USA might be REAL expensive.

    There are some quality speakers available from Italy that sound similar so I am told.

    If you get stuck, send me an email and i'll help you out.
  15. Funkengrooven

    Funkengrooven Turn it down? You gotta be nuts!!

    I beg to differ....ALL mine are home built and I be damned if they cost me the $950.00 US that it would have taken to buy a Bergantino..

    here is the cost breakdown:
    2 blown JBL K-140 15's from ebay incl shipping $125...
    cost of aftermarket reconing for both $175.00
    4 sheets of 3/4 B/C plywood $100.00
    misc hardware, glue, nails and connectors $50.00

    total price....$450.00 half of the Berg and i have two 1x15 ported kickass boxes with JBL's to show for it.

    try buying any 2 cabinets with fresh Alnico JBL's in it for that much...

    if you ask the right questions and go slow you will be successful, if you rush you will spend a lot of frustrating time and money to get it wrong anyway....

    Ask Thor..his Cabinet turned out real nice.

    measure twice, cut once...good advice from an old carpenter..

    Take a look at the 2x12 behind the drummer, that is the first cabinet i ever built. I was 16 years didn't rattle or buzz..and yes it was loaded with JBL D-120's...some things never change... ;)

    Attached Files:

  16. Thor

    Thor Moderator Staff Member Gold Supporting Member

    Good advice from FG.

    Thanks for the compliment btw :)

    Zoot, read through the thread on the DIY rebuild in my sig.
    It deals with pretty much all the same issues you will
    have to cover.

    The difference is that you get to design your box from
    scratch, I retrofitted a big ole dawg guitar cabinet,
    essentially stripped it and just used the box. So I had
    to adjust my drivers to my box volume, you can pick
    your drivers first, and build the close to perfect box.

    The WinISD program was very helpful, once I downloaded
    it and played with it, I found it easy to use. That was a great
    tip, don't build a box without running through the specs

    So do all the stuff, research drivers and their cost, pick
    ones that perform as you like ( or can afford) and
    calculate all the parameters. Then plan the box size.

    Then you will have to source all the necessary materials.

    Once this is done, you may find yourself altering the
    dimensions slightly to get the most efficient use of
    the plywood. Good plywood is not cheap, so you don't want
    to waste it.

    Lastly put together the cab you always wanted.

    I found it to be a very satisfying and rewarding experience.
    I ended up with a nice Delta 12 LF x2 upgrade for about
    $160 USD iirc. I also learned a lot about what I can do for
    short money with good projects. F.E. I picked up a cracked
    SWR 4x10 cab with what I think are PAS drivers on TB for 175,
    which will either get stuffed into a new cab, repaired or
    broken down to 2 2x10's, the possibilites are endless.
    It has all the hardware, needs a little wood. When I am done
    with it, it will be top notch!

    Anyway, I just wanted to give you a little motivation.

    If you do it, take some pics and post them for the benefit
    of potential builders like yourself. And I'd love to see the work
    in progress as well!
  17. Eric Moesle

    Eric Moesle Supporting Member

    Sep 21, 2001
    Columbus OH
    I haven't heard your cabs, FG, but curious as to why you price compare them with Bergantino instead of someone like Dr. Bass or Avatar, which would be cheaper, of course. ;)
  18. BruceWane


    Oct 31, 2002
    Houston, TX
    Unless you also have the exact same speakers to work with, this isn't really a good idea. Just because the diameter of two speakers is the same doesn't mean they will work well in identical cabinets; you may get lucky, but more than likely your results won't be too good.
  19. Avatar will sell you an empty cab for around $150. It is complete, minus the speakers and horn.
  20. Thor

    Thor Moderator Staff Member Gold Supporting Member

    Unless you model the speakers with WinISD and adjust the box dimensions accordingly.

    Or Steelsound. However, the shipping charges to the
    UK might add a bit of cost to that, then there is the
    question of customs duty. And that's if Avatar even
    will ship
    an empty box internationally.

    Then the drivers still need to be sourced, and modelled to
    Avatar's empty cab. He is better off building a cab to
    suit the drivers, IMHO, given all that.