Box build for 2011 Cruze Eco
 

I've kinda already got an idea of what I wanted to do for the sub box. I wanted do build a ported box tuned around 27Hz, but maybe I should do something else idk. Here's some info.

1. Make/Model of Subwoofer
Hifonics BRZ15D4 (15")

2. Subwoofer's T/S parameters (Qes, Qms, Fs, Vas, Sd, Xmax, and RMS Power handling)
Qes: 0.58
Qms: 3.5
Fs: 21Hz
Vas: 200L
Sd: 0.08sqM
Xmax: 15.5mm
RMS: 600W (I'm pushing 500W to it)

3. Where in the trunk you plan on placing this sub
Plan on making a rear-firing box. Want the back of the box to be up against the rear seats inside the trunk, perhaps even have a slanted back to the box.

4. Make and model of your subwoofer amplifier
Kenwood KAC-8105D (1000W max, 500W RMS @2 ohms)

5. Types of music you primarily listen to
Rap/Hip-Hop, Electronic/Dubstep/Trap/House/EDM/etc., music with heavy bass in the 25Hz-45Hz range

6. Primary goal for performance (Sound quality, SPL, best use of a box you already own, smallest box possible, etc.)
The box can be as big as is necessary, pure SPL for longer and heavier bass notes (rap&electronic bass) from around 25Hz-42Hz.

What do you guys think? Right now I'm looking at building a ported box of 6cu. ft tuned to 27Hz.

Hifonics recomends 2-4 cubic ft. ported.. you wont need more then 4.
i'd highly suggest tuning a bit higher above 30hz

I punched in the T/S in winisd and peaks high around the 40hz+ range but doesn't require alot of port area minimum 45.84in^2.

I would do 5 cubes net tuned to 30hz it will play down to 25hz due to the low FS and your cars cabin gain.

I can help you with a box design just give me your maximum dimensions, LxWxH.

A 4cu. ft. box tuned to above 30Hz isn't going to work for me since I intend to play notes as low as 25Hz.

5cu. ft. tuned to 30Hz seems reasonable. Here's the lowdown:

I'm looking at either a 4-5cu. ft box. The 4 drops below +0dB at around 30.5Hz tuned to 28Hz, the 5 drops below +0dB at around 28Hz tuned to 28Hz. Which one do you guys think? I will probably work with both 1/2 MDF and 3/4 MDF so the box is not as heavy. Here's the info:

Box type : Vented
Box size : 5.000 ft^3
Tuning frequency : 28.00 Hz
Vent : 1 vent(s)
5.54 in length for each
4.00 in round


Relative
Freq Gain SPL
[Hz] [dB] [dB]
20.00 -8.85 106.14
21.00 -7.51 107.48
22.00 -6.25 108.74
23.00 -5.06 109.93
24.00 -3.94 111.05
25.00 -2.88 112.11
26.00 -1.89 113.10
27.00 -0.96 114.03
28.00 -0.09 114.90
29.00 0.70 115.69
30.00 1.41 116.40
31.00 2.04 117.03
32.00 2.58 117.57
33.00 3.04 118.03
34.00 3.40 118.39
35.00 3.69 118.68
36.00 3.90 118.89
37.00 4.04 119.03
38.00 4.12 119.11
39.00 4.15 119.14
40.00 4.14 119.13
41.00 4.11 119.10
42.00 4.04 119.03
43.00 3.96 118.95
44.00 3.87 118.86
45.00 3.77 118.76
46.00 3.67 118.66
47.00 3.56 118.55
48.00 3.45 118.44
49.00 3.34 118.33
50.00 3.24 118.23

Number of drivers : 1
Box type : Vented
Box size : 4.000 ft^3
Tuning frequency : 28.00 Hz
Vent : 1 vent(s)
7.66 in length for each
4.00 in round


Relative
Freq Gain SPL
[Hz] [dB] [dB]
20.00 -9.68 105.31
21.00 -8.47 106.52
22.00 -7.33 107.66
23.00 -6.25 108.74
24.00 -5.24 109.75
25.00 -4.27 110.72
26.00 -3.35 111.64
27.00 -2.48 112.51
28.00 -1.65 113.34
29.00 -0.87 114.12
30.00 -0.15 114.84
31.00 0.53 115.52
32.00 1.14 116.13
33.00 1.69 116.68
34.00 2.18 117.17
35.00 2.60 117.59
36.00 2.96 117.95
37.00 3.25 118.24
38.00 3.48 118.47
39.00 3.65 118.64
40.00 3.78 118.77
41.00 3.86 118.85
42.00 3.90 118.89
43.00 3.91 118.90
44.00 3.89 118.88
45.00 3.85 118.84
46.00 3.80 118.79
47.00 3.73 118.72
48.00 3.66 118.65
49.00 3.58 118.57
50.00 3.49 118.48


As you can see, the 5cu. ft box shifts the low end just a tad bit lower and spikes a little harder right around 38-42Hz, but only by .3-.4dB. I'm starting to think that the 4cu. ft box might be the way to go, just not sure what to do.

4cu. ft tuned to 28Hz or 5cu. ft tuned to 30Hz?

Help :confused:

Also, I'm going to want to build a box with a slanted back.

5 cubes net single 6" aeroport stock length of 17" will be tuned to 27hz. If weight is of concern use 3/4" Birch or Arcauco Plywood both will be lighter than MDF.

Your sub loves huge boxes