box design advice

[Ritch40]

This is a design I came up with for an Obsidian 12v2. I plan to give the sub the full 600Wrms.

This enclosure will be mounted to the back wall of the sleeper on my semi. I am planning to build an amp rack above the enclosure.

I do have some questions and concerns with the design. Please bare in mind that I am very new to using software such as winISD so I don't fully understand how what i am seeing on the graphs will translate to real world function.

To me sound quality trumps spl.

gross box volume is 2.025cuft

net volume is 1.77cuft

port opening is 12" x 2" x 25.9" long tuned to 32Hz. Rear port velocity tops out around 95ft/sec @ 29Hz

-The top of the port is just over 2" away from the top of the enclosure, is this enough space to work right?

- Would it be better if i raised the tuning a bit to give more clearance?

- Will this sound good in my cabin (as best as you can guess (I am fairly certain not many of you have done an install in a semi))

- Is there anything i should alter on this design?

- Do the response curves on the graph look good?

- Does anyone have any suggestions?

Thank you in advance for any suggestions and advice!!

I should also add that most of the music i listen to is rock, metal and country

[timc31610]

Where and how will you be mounting the box? I would think sub out port to the side firing into the corner may give a better response than just firing into the open area.

[timc31610]

And, I have never seen a sub in a semi! lol. Ill be tuned into this. Also, be careful on this site, before you know it you will be asking how to wall of your sleeper with 10 15" subs and 30k watts of power...lol

[Ritch40]

there is a shelf that comes out from the back wall

so box will be on the shelf against the back wall and bolted into place. With the way everything has to be done here, The sub and port have to fire in the same direction.

[Ritch40]

there is a shelf that comes out from the back wall

so box will be on the shelf against the back wall and bolted into place. With the way everything has to be done here, The sub and port have to fire in the same direction.

[Ritch40]

lol.....well considering the fact the bed i sleep in many nights is back there, i wont be walling this off....lol

that said.....me and a few other friends of mine that are all truck drivers have done some installs into them.

i just want to make sure everything i do from here on out sounds right and looks right.

Sorry for my previous post being doubled. i am not quite sure how that happened

[Krakin]

Honestly you might want to try out a sealed enclosure first.

1: It is A LOT more forgiving in the designing.

2: You can easily find if you have some bad resonances in your cabin that will affect the response of the sub.

3: You can save on a lot of space.

4: You can find things that will be annoying when the bass hits and rattles.

5: You don't want too loud in your truck, because WHEN your mirrors start shaking it can be very hazardous for you and others you may not see.

6: If I recall correctly those subs are more inclined to sealed enclosures anyway.

[Ritch40]

krakin,

as you saw on the graph, i am modeling a sealed box as well. I just like the increased volume aspect of the ported in this case. Ialso do like the fact the ported box seems (according to the graph) to reach down a little lower.

I do currently have 2 15's in here so the rattles and such i am taking care of. I have learned over time that 15's just arent the best choice for the music i listen to. plus it will be nice to get rid of the 10cuft box i currently have back there.

[Krakin]

In WinISD I strongly looking at the Group Delay page.

This will let you see how fast the sub can go from one frequency to another.

Sealed will be pretty dang fast. Which will help with metal where you have things such as double kicks as well as a bass guitar.

If you are looking at mainly those types of music and not anything that requires a producer to create synthetic low end bass then you won't really be having much of any notes hitting lower than 40 Hz. IIRC the lowest note for a bass guitar is 44Hz fundamental frequency.

If you give me some time I can through that sub into WinISD and mess around with it again.

[timc31610]

^ Now you have some real help, I was just filling in until Krakin showed up...