Hey Phil! Kicker sub enclosure

[Razzman]

Quick question for ya, I'm adding a Kicker Comp10 marine rated sub and the specs call for a minimum of 1.0 cubic foot / maximum of 2.5 cubic foot sealed enclosure. I'm pushing it with an Orion HP2400 bridged mono at 225 watts. What cf size would work best for this sub and allow some good bass? I was thinking somewhere in the 1.5 cf range?

[philwsailz]

Quick question for ya, I'm adding a Kicker Comp10 marine rated sub and the specs call for a minimum of 1.0 cubic foot / maximum of 2.5 cubic foot sealed enclosure. I'm pushing it with an Orion HP2400 bridged mono at 225 watts. What cf size would work best for this sub and allow some good bass? I was thinking somewhere in the 1.5 cf range?

maybe...

You going sealed or vented?

[philwsailz]

BTW, if you have not purchased the sub yet, consider the KICKER SKM10.

It is a sealed rotomolded enclosure with a KM10 marine sub already installed.

It would be perfect for the power you are talking.... (as would the C10, BTW)

[Razzman]

Sealed. I got the sub for free, my local dealer comped me one for bringing him a bunch of customers.

I've installed it in my current .75 cf box but it doesn't hit as hard as the one i installed in my buddies boat in a 1.0 cf box and he's pushing it with a RF 450.4bridged at 200 watts. I tried it with and without polyfill and it sounds better without. Any thoughts?

[philwsailz]

Sealed. I got the sub for free, my local dealer comped me one for bringing him a bunch of customers.

I've installed it in my current .75 cf box but it doesn't hit as hard as the one i installed in my buddies boat in a 1.0 cf box and he's pushing it with a RF 450.4bridged at 200 watts. I tried it with and without polyfill and it sounds better without. Any thoughts?

That woofer will work better in a 1.00 - 1.25 cu ft sealed enclosure.

.75 is on the smallish side... Sounds kinda "one-note-ey" doesn't it?

See about working on a larger box. Shoot for 1.25 roughly gross, which should net you roughly 1.15 net, or near that...

Keep us posted!

[Razzman]

Thanks Phil! I'll let you all know how it goes.

[Razzman]

Oh yeah, what's your take on the polyfill anyway?

[philwsailz]

Oh yeah, what's your take on the polyfill anyway?

It works, certainly measurably, and I believe it makes an acoustic difference as well some of the time that lots of us can hear and describe.

Here is the issue, (my opinion) with it in a marine installation: I believe that the difference is audible in critical listening environments; a boat is outside of that definition in my opinion.

Polyfill will retain moisture by nature, and while it can help a little with acoustic issues, it can cause problems if it ever gets wet, by immersion, (if that is the case you have other issues) splashing, or just environmental humidity.

Use polyfill.... in your home speakers.

I would recommend leaving it out of the boat; the system will last longer.

[Razzman]

Thanks, one more question and then i'll quit bugging you!

Because of height limitations clearing under the dash (closed bow) i can only have a max box height of 12.5". So i'm looking at a box of roughly 12.5h x 14.0w x 16.5 d which results in 1.194 internal volume when made with 3/4" mdf. This also takes into account a 60cc/3.66ci displacement. Does the actual shape of the box matter that much? Like in this case where the box is a lot longer than height/width?

[philwsailz]

Thanks, one more question and then i'll quit bugging you!

Because of height limitations clearing under the dash (closed bow) i can only have a max box height of 12.5". So i'm looking at a box of roughly 12.5h x 14.0w x 16.5 d which results in 1.194 internal volume when made with 3/4" mdf. This also takes into account a 60cc/3.66ci displacement. Does the actual shape of the box matter that much? Like in this case where the box is a lot longer than height/width?

The ideal ratios are .618 to 1.00 to 1.618; using phi, or the golden number.

That being said, you FOR SURE will not hear any difference... Your dimensions are absolutely fine...

[philwsailz]

Thanks, one more question and then i'll quit bugging you!

Because of height limitations clearing under the dash (closed bow) i can only have a max box height of 12.5". So i'm looking at a box of roughly 12.5h x 14.0w x 16.5 d which results in 1.194 internal volume when made with 3/4" mdf. This also takes into account a 60cc/3.66ci displacement. Does the actual shape of the box matter that much? Like in this case where the box is a lot longer than height/width?

So you know, a cube is really the worst shape... Almost...
It is the worst shape that is easily built.

A sphere is horrible in my opinion, but I doubt you will mess with that construction...

[Domsz06]

what's the best shape?

[philwsailz]

what's the best shape?

Now understand, at this point we are talking pure theory...

The golden ration above provides the best random dispersion of standing-wave frequencies; less ringing, if we can call it that.

Better yet, if we can employ phi as a general guideline, while at the same time creating an enclosure with no parallel walls we will have even less issue with standing waves. There basically can't be any standing waves in the enclosure if there are no parallel walls.

Take these two statements above and build a box using them as a guideline, and you will have what many or most consider the "best" subwoofer enclosure...

Some would argue that a sphere has no parallel walls, but if we consider the inside of a perfect sphere as a bunch of little flat areas, we are guaranteed that every little flat area has a similar flat area exactly parallel to it at exactly the other side. Plus, the distance between these two flat areas is EXACTLY the same as the distance between every other pair of tiny little flat parallel areas. Bad bad bad.....

[Razzman]

So just for giggles then a hex would be a good design then? Not that i'm going that far! Just curious.

[philwsailz]

So just for giggles then a hex would be a good design then? Not that i'm going that far! Just curious.

A true hex would be not as good as the box you have called out above.

Your box has only three pairs of parallel surfaces, and they have different distances between all three.

A true hex would have four pairs of parallel surfaces, three of which would be all exactly the same distance apart. bad...