Volume for a sealed 4x10 bass cab?

Discussion in 'Amps and Cabs [BG]' started by HPH, Jun 6, 2019.

  1. HPH

    HPH

    Nov 14, 2017
    Hello.
    I am making a 4x10 sealed 2 chamber bass cab in lexan/polycarbonate.

    How much volume does each chamber need? Are there any technical info on the speaker elements that say how much volume each element needs?

    Or is it a specific volumnumber for all 10" speaker elements?

    Does anyone know how much volume there is in each chamber on 8x10 ampeg svt? Because then I could just copy that volume.

    What is most dangerous? To little volum or to much?


    Thanks.
     
  2. The best volume depends on the speaker you're using. If you want a quick and dirty cab, you could get four eminence legend b810s and literally build the bottom half of an Ampeg 810e and get a useable 8 Ohm 410.
     
  3. Rick James

    Rick James Inactive

    Feb 24, 2007
    New Jersey
    The technical info is Thiele/Small parameters ( https://www.eminence.com/support/understanding-loudspeaker-data ) which are plugged into a loudspeaker modeling program ( WinISD - Linearteam , for example). Lexan is a poor choice for speaker cabinets. It's far more flexible than high grade plywood, so it would take extensive bracing to make the cabinet stiff enough, and it's very expensive. Assuming you want to use it to see inside that doesn't work either, as speaker cabs must be lined with acoustic damping, like foam or polyester, and sealed cabs can require being totally filled with damping. That's why no one makes or sells Lexan speakers.

    You could, but you can't assume an existing cab is ideally sized. Most are smaller than ideal for marketing reasons. For instance, the ideal volume for the B810 driver in a sealed cab is 11 cubic feet...each. You can use it in a smaller cab, but when you do you lose low end extension and create midbass boom.
     
    stigbeve likes this.
  4. deff

    deff

    Oct 15, 2018
    Gloucester, MA
    Why? It will be heavy as hell, maybe prone to shatter, etc. etc. I get the looks thing, but as someone who works in a materials lab, this seems suspect at first blush.
     
  5. HPH

    HPH

    Nov 14, 2017

    OK so 11 cubic feet for each 10"? So like ideal volum for 4x10 is 44 total? 22 in each chamber?
     
  6. Bill Staudt

    Bill Staudt

    Jun 18, 2002
    I think 1 cubic foot per driver. My old flatback SVT was approx. 24.5 x 10.75 x 12.5 in each internal chamber.
     
  7. JRA

    JRA my words = opinion Gold Supporting Member

    :D


    even when i'm drinking i don't have thoughts like these. :laugh:
     
    bassinflorida likes this.
  8. JRA

    JRA my words = opinion Gold Supporting Member

    OP: forgot to wish you "good luck" with your project! :thumbsup:
     
    HPH likes this.
  9. Rick James

    Rick James Inactive

    Feb 24, 2007
    New Jersey
    For a Q of 0.7, yes. Not that a Q of 0.7 is necessary, up to 0.9 can still sound pretty good, but in the 1 cu ft recommended above the B810 Q will be 1.1, so it will boom like the Fourth of July. I know you don't know what Q means in this context, but that's part of the problem. It's part of the vocabulary you must be in command of to design your own speakers that work really well, as opposed to a random driver in a random box that will sound like Forest Gump's box of chocolates, because you'll never know what you're going to get.
     
    Munjibunga likes this.
  10. Bill Staudt

    Bill Staudt

    Jun 18, 2002
    Make sure you put a trailer hitch on the 44 ft3 410 cab. I'd also recommend dual axle.
     
    HPH, Pulverizor and chadface like this.
  11. lz4005

    lz4005

    Oct 22, 2013
    If it's good enough for Stig and MCA, it's good enough for OP.
    [​IMG]
    [​IMG]
     
  12. What model speaker are you using?

     
  13. Wasnex

    Wasnex

    Dec 25, 2011
    If you take a look at various Eminence drivers at Parts Express, most if not all of them will have a link to download a suggest cab design document that will show various tunings.

    This link should open up to Eminence 10" woofers.

    Pro Woofers, Subwoofers & Midrange Speakers in the Speaker Components Department at Parts Express | 31

    Click one of the drivers and then scroll down. On the left side of the page you should see a heading titled Manuals and Resources where you can download datasheets and available cab designs.
     
    xaosbass likes this.
  14. HPH

    HPH

    Nov 14, 2017

    OK thanks for good info, but just so I get this right,
    "Eminence Delta-10A 10" Midrange Driver 8 Ohm" from www.parts-express.com!

    Is this speaker element good for punchy sound? Or do u recommend another?

    It says 0.18 cubic feet, that's 5 liters volum per speaker element (and is driver same as speaker element).

    I am going to use some old peavy speakers at first, but I will change to eminence later, so I will build the cab for eminence.

    8 ohm is alright?

    Gonna design it so it fit a flight case with wheels so I can roll it easy around, with good paddings and protection.
     
    DiscoRiceJ likes this.
  15. HPH

    HPH

    Nov 14, 2017
    Do you got any suggestions on what eminence speakers that will give punchy sound?
     
  16. HPH

    HPH

    Nov 14, 2017
    Sorry I am from Norway, what are those measurements in?

    Inches? 24.5 x 10.75 x 12.5 = 53.94 liters?
     
  17. Bill Staudt

    Bill Staudt

    Jun 18, 2002
    Yes, those measurements are in inches.
    About 1Ft3 or 28L per driver for an Ampeg style cabinet.
    The Eminence Legend B810 mentioned above would be a very good choice, in my opinion.
     
  18. Wasnex

    Wasnex

    Dec 25, 2011
    That driver is recommended for vented enclosures.

    Also I checked the link I gave you and it only shows the pro sound drivers...sorry for the oversight.

    This link is filtered to show the bass guitar speakers, although I think one guitar speakers is thrown in.

    Guitar Speakers & Bass Guitar Speakers in the Speaker Components Department at Parts Express | 37

    Some of the bass drivers have plans for sealed designs like the BP102, B102, and B810. I suggest taking a look at the frequency response charts in the data sheets to see what the mids and highs will sound like, and then compare the cab design documents to see which will give the low frequency response in the size of cabinet you want to make.

    Also you can find free downloads and online calculators that allow you to input the driver parameters from the datasheets so you can model the driver response in whatever size box you want.

    Here's an example of an online calculator for sealed boxes. HiFi Loudspeaker Design

    I tried this ported version and it was a bit futzy, but it seemed to work. HiFi Loudspeaker Design


    Regarding the impedance. If you use a series/parallel wiring scheme the total impedance is the same as a single driver. I.E. a 410 using an 8 ohm driver will have an 8 ohm impedance.
     
  19. seamonkey

    seamonkey

    Aug 6, 2004
    Does it really have to work?
    Build a stage prop that you can put on top of a real cabinet.
    Or go direct and just have the stage prop behind you.
    Use lighter cheaper poly and 3d print and plate a cool looking driver. Add some LEDs
    Or use car speaker with all the chrome.
     
    Rick James likes this.
  20. Wasnex

    Wasnex

    Dec 25, 2011

    Audio techs in one of my bands uses to have a little device from some high end audio company. The device had a chimerical name, a couple of gold plated switches, and was made of some really nice figured wood. It didn't actually do anything, but I think it was somewhat of a status symbol to own and display one.