Does anyone know of a good website for speaker physics?

Discussion in 'Amps and Cabs [BG]' started by Ericman197, Apr 13, 2004.

  1. Ericman197


    Feb 23, 2004
    I was all set on getting an Accugroove Tri-210L and Whappo Grande, when I had an interesting idea. While I'll probably still get the Tri, I might make my own subwoofer and eventually my own cabs for various other purposes. From what I've heard, it's relatively easy to do this if you know the Thiele small parameters and know the various necessary calculations. What I'm wondering is, aside from the obvious saws, hammers and such, what equipment would I need? What calculations are necessary? I'm fairly decent at physics, so if I could find a site that explained the calculations and such, I could probably make a go of it. I'm not very good at woodworking, but I might sign up for that class next year. My real problem is that I need a relatively loud and deep subwoofer that's easier to transport than the Grande. I'd really like to get the Grande, but it's just a bit too big.
  2. This guy has all the equations:

    A program to crunch numbers for you if you change your mind (plus it has graphs):

    Glue (liquid nails/beats the nail works well), then either screws or clamps to hold the box together, sealer for the inside to keep the seams airtight (silicone is best, plain window caulk works too though)...

    A very worthy project! I've come to the same conclusion: that custom is really the way to go to get all your needs met. Good luck and let us know how it goes!
  3. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Gold Supporting Member Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
  4. ESP-LTD


    Sep 9, 2001
    If you want a true sub (nothing above 200hz or so) you might consider car audio subs. There is a complete range of very nice rubber surround subs in all price ranges. Just bring plenty of power as their sensitivity is quite low.

    JBL Car Audio has basic plans included (under "boxes and parameters").

    As in most endeavors, you can fudge a lot on the fancy math if you overbuild your design (that is, Fs below box tuning frequency, AND below your lowest expected note).
  5. Ericman197


    Feb 23, 2004
    Thanks, I'm going to try to build it some time over the next couple of months, and then I'll pair it up with the AG Tri-210L. I really have no idea how it'll come out or whether it'll mesh with the Tri, but I think it's a worthwhile endeavor. If it does work, maybe I'll take wood shops and start making custom cabs for mad cheap prices :cool:
  6. Ericman197


    Feb 23, 2004
    Ok, did some research... my main problem is that I sort of know what the Thiele Small parameters are and what to do with them, but I've yet to actually find a place to buy quality speakers. JBL sells mostly car audio speakers that are meant for small sealed enclosures with a 12dB/octave rolloff which is counteracted by the car itself. What I'm looking for is a speaker that'll give a high output ( 95+ dB ) and sound deep in either a sealed or ported cab design. For now, I don't want to bother with a passive radiator, transmission line, 4th/6th order bandpass, etc. I'll continue to try out different speakers though... I'm going to try some Eminence models now.
  7. Petebass


    Dec 22, 2002
    QLD Australia
    Download Bgavin's spreadsheet. It's got heaps of info. Sort it by whatever column you like to get a list of potential drivers. If I were you, I'd be sorting by cab volume (Vb), then by Sensitivity (SPL 1W). You may also want to find out the sensitivity of the Tri 210 because if you're not careful, one speaker cab could drown out the other. Get the sensitivities close and they should blend together.

    You've mentioned Eminence, they make a some great drivers and some not so great ones too, so choose wisely. Actually the same can be said for any speaker manufacturer.......

    If you like JBL's pro Audio gear, the check out Beyma (Spain). You should also look at Selenium, PAS, and B&C. I've also used cheap P.Audio speakers and found they're not as bad as their cheap prices would suggest.

    I've got some great websites bookmarked - at home......I'm at work now so I'll have to drop them in later.

    You should also read "The loud Speaker Design Cookbook" byt Vance Dickason. It's the speaker builder's bible.
  8. These guys have excellent prices and a pretty decent selection to boot-

    For odds-n-ends (corners, jack plates, etc...) I would try-

    They have a great selection of drivers but their prices aren't as good as (usually). Researching and deciding on a driver is the hardest part! Follow Petes suggestion and check out bgavins spreadsheet. He's done a lot of the work already. There are some pretty knowledgeable guys around here too so ask questions and you'll do just fine. Let us know what driver you decide on!