# Jbl gti speaker box



## kpt.klo (Jul 28, 2017)

Need advice for jbl c608 gti box.
I'm not sure to go sealed or vented with this unit in a convertible. I only need it to play down to around 80 hz where a jbl w12gti in a vented box will take over.
Will a sealed box work best as "kick bass"?
Box size (liters)?

Please have in mind that this is a covertible, so the unit is playing out in free air with no room gain.

I'm thinking of using 2 sets behind the backseat , but I have severel sets in stock, so I could use 4 sets and go isobaric, to save space.

Front: jbl 404gti + c608gti (woofer only). Center: jbl 404gti. Rear: jbl 404gti.
Pioneer 80prs + Jbl MS-8 dsp + rainbow 1.8 dsp (for front system) phoenix gold bass cube + jl audio amps (2x HD600 + HD1200 + 2X XD400) and some more... 😊


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## lithium (Oct 29, 2008)

get some T/S specs for the woofer and maybe someone can help model them up for enclosures size. Depending on space, you could go sealed or ported in some behind/under seat enclosures if you have room.


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## kpt.klo (Jul 28, 2017)




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## kpt.klo (Jul 28, 2017)

I'm not that good at calculating speakers.


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## lithium (Oct 29, 2008)

blue is 0.25 cu ft = .725 qtc (xmax reached with 25 watts no filters)
green is .5 cu ft @ 50 hz ported = (xmax reached at 25 watts no filters (will require high pass below tuning freq)
Read is 3 cu ft "infinite baffle" like a door, 80hz hpf and 50 watts to avoid xmax


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## kpt.klo (Jul 28, 2017)

Thank you Lithium. That is perfect. 
It Looks to me like there is no way to go, but vented. The sealed would need some heavy EQ when playing outside the car cabin, if I want to cross over to a sub @ 80 hz.


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