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Thread: Air space formula?

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    Air space formula?

    Does anyone here know the formula for calculating airspace. Im putting 4, 8W3v2's under the back seat of my ex-cab truck and i know the box needs to be 4 cubic feet but now i need to figure the actual deminsions of the box. any help is appreciated.

    Will
    Daily driver: 2001 Mustang Cobra- Eibach suspension, Tokico struts, Maximum motorsports full length subframes, 4.10 gears, MGW short throw shifter, JLT cold air intake, Bassani X-pipe, Bassani Catbak, full sound system

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    length " x hieght " x width " = cubic INCHES

    Cubic Inches/1728 = Cubic Feet.

    Now you have to factor for material thickness, woofer displacement, & dividers

    So if you are building the box from .75" mdf then all of your LXHW measurements get decreased by 1.5" (2 panels of .75")

    If you have a divider between a pair of subs then HXWX.75" = space divider takes up must be subtracted x # of dividers

    Most better woofer companies give recommended volume in "net" meaning you dont worry about the displacement of the woofer.

    Rob W

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    since im building a box for 4 subs should i put a divider in the center and in a way have 2 subs per box?

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    depends on the sub & depends on the amp(S).... either 1 divider 2 subs per box or 3 dividers 1 sub per volume

    what amps are you running? what subs? what music? are the enclosures ported or sealed?

    Rob W

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    4, 8w3v2's jl audio, ppi dcx 500.1, i also run ADS seperates up front on a ppi pcx 280. Alpine head unit and seriously thinking of switchin to clarion

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    Alpine to Clarion????? Why in the WORLD would you down grade so much? unless you want Fluff over performance.. I am never this critical... but Clarion (even Pro-Audio (cough snicker) level is a HUGE performance down grade... Unless you paid $199 retail for the alpine... sorry... I know a little harsh... what Alpine do you have now?

    with what you have amp & sub wise... do a wide open box... be sure all of the woofers are within 1" of each other if not touching... best will be a a row of 8" woofers with the frames touching all in a one big open chamber... its called acoustic coupling... as long as you PPI can handle the load... drop it as low as it can go....

    Are the 8" woofers dual 2 or dual 4 ohm woofers?

    Rob W

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    Alpine 9835, reason being is radio reception is not great, but i have ipod interface that needs to be put in and i plan on upgraded so XM so i still havent made that decision. Im really looking forward to having this done, i miss having a complete system.

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    I would look at why the radio reception is bad... poor ground on the radio, bad antena connection, poor antena ground on the fender... etc...

    Once you have XM or Sirius you will never listen am//fm again... LOL Alpine s the only one with a complete file-interface control over iPod right now... file scroll, searchm edit.. all from the screen... very sweet!

    Rob

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    Unless you plan removing your rear seat completely you will never fit 4-8w3v2's under the seat i have done the math. Best possible it 1.83 cu ft and I planned for this using fiberglass enclosure. That is a long way from 4 cu ft. There are a few companies that make seat relocation brackets but not sure of fit and quality.


    I suggest the 2-10w6v2's. These speakers only require 1.25 cu ft.

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    Im goin to build a custom mount setup for my rear seat, being an extendid cab its not all that hard. And i love the W6's but their to expensive and to deep to do what i want to do with them. The last time i did i system in this truck i had 2, 12W3's ported and still had a back seat so i dont see a reason why i cant do 4-8's.

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    Ok, I was not sure if you were moving or replacing the seat. Good luck. I would like to see the finished product.

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