View Full Version : Design questions for 12" Kicker L5 in ported box @ 33 Hz

01-27-2014, 09:23 AM
Hey guys, I was hoping to get some box dimensions for this set-up:

Vehicle : 1997 Toyota 4runner
Location in the vehicle: Back
Space available (Length x Width x Height): Lots
Subwoofer make and model: Kicker L5
Subwoofer Size: 12
Number of Subwoofers: 1
Type of Port (Kerfed, Slot, Aero, etc.): Slot
What type of music do you like?: alternative/electronic
Is your goal SPL or Everyday Music?: Everyday, but I like it loud
Tuning Freq (Hz): 33 (this is a number I've picked from doing a little research, please feel free to offer better suggestions)
Volume : ???
Questions: I am running an alpine MRX-55 to this sub alone, and it should be good for around 500 watts @ 2 ohms. I have the space to build almost any size box, so I am looking for suggestions. What size do you recommend for this sub? Thanks in advance,


01-27-2014, 10:51 AM
That sub won't do well tuned that low. It's an SPL oriented sub that wants a lot of air space to do loud at ~40Hz and it isn't much use for anything below that.

If you already have it, I'd just build a box according to Kicker's recommended specs or just pick up a prefabbed ported box. Those are normally tuned high anyway so it would save you some time and effort.

01-27-2014, 03:10 PM
Thanks for getting back to me so quickly. I am still somewhat unsure of what overall size I should go with. Kicker suggests a 3.25 cu ft box for an SPL set-up tuned to 41 hz, but I'm reluctant to go full SPL. I still want to be able to enjoy music on a daily basis, but I also want to be able to hit pretty deep. I got the sub for super cheap so I just want to make the best of it, if you know what I mean.

01-27-2014, 05:47 PM
Gonna agree, 33hz is is too low for tuning - I'd aim more for 36-38hz for electronic/dubstep, or 40-42hz for rock/country.

01-28-2014, 01:26 AM
You guys are totally right, the more research I do, the more it looks like 37 is where I want to be. That being said, I still have two questions:

How much volume do you recommend?

Is port volume included when calculating total volume? (i.e., most people recommend a 3 cu ft box, so would my actual box be more like 3.5ish, depending on port size?)

01-28-2014, 09:21 AM
What year L5?
D4 or D2?
From the L5 Manual: "For the vented enclosures the displacement of the port must be calculated and added to the internal volume of the final design".

01-28-2014, 02:49 PM
2008 L5


Thanks for finding that quote for me, makes sense!

01-28-2014, 04:29 PM
Based on Kicker's published specs, an enclosure size of 3.25 cubes per woofer (not counting port volume) would yield a Fb of 39.9 hz.
Going larger would drop that down a tad - but you also trade off power handling.