Scion tC 150db box design

[shizzzon 461]

This is a goal to reach 150db tuned for a daily driver.

I've been doin some measurements and have came up with a box design that has me smiling and this will be the last box i will build for the car... unless i downgrade later.

This is my last attempt to try and reach 150db with a daily tuned setup and i'm crossin my fingers because this is only with 2 15s and 4,400w of power.

Here is the wild design-

Remove back seats, where back seat was, install a wall there sealed off from the hatch area.

Now, i have 33" of depth from this wall to the back of the front seats.

The box design would consist of 2 15s ported facing toward the wall. There is an 8" gap from the front baffle to the wall. Both subs and port face the Sealed Wall.

This 8" gap acts as a loading area. The output would then be dispersed around both sides of the box through tunnels consisting of 5.5" wide per side and approximately 9" tall at the beginning and then dispersing everywhere by the time it's halfway down both sides of the box.

The top of the box does NOT touch headliner... it's close, probably 0.5" in some areas and 1.5" away in other areas.

I'm debating whether i should allow the air to only flow around the sides of the box or the itty bitty ass opening at the top of the box.

the box is 33" wide.

It gets 44" wide toward the bottom to increase internal volume properly.

Because it gets wider, this is why the air flow around the box isn't simple as you can see.

I should have the best of both worlds correct?

A smaller cabin to pressurize and a loading area on top of that.

Box would be 9.0cuft tuned to 40hz using 2 Original AQ HD315s with 154sqin of port and 4,400w of power.

[sound=vibration 34]

This is a goal to reach 150db tuned for a daily driver.

I've been doin some measurements and have came up with a box design that has me smiling and this will be the last box i will build for the car... unless i downgrade later.

This is my last attempt to try and reach 150db with a daily tuned setup and i'm crossin my fingers because this is only with 2 15s and 4,400w of power.

Here is the wild design-

Remove back seats, where back seat was, install a wall there sealed off from the hatch area.

Now, i have 33" of depth from this wall to the back of the front seats.

The box design would consist of 2 15s ported facing toward the wall. There is an 8" gap from the front baffle to the wall. Both subs and port face the Sealed Wall.

This 8" gap acts as a loading area. The output would then be dispersed around both sides of the box through tunnels consisting of 5.5" wide per side and approximately 9" tall at the beginning and then dispersing everywhere by the time it's halfway down both sides of the box.

The top of the box does NOT touch headliner... it's close, probably 0.5" in some areas and 1.5" away in other areas.

I'm debating whether i should allow the air to only flow around the sides of the box or the itty bitty ass opening at the top of the box.

the box is 33" wide.

It gets 44" wide toward the bottom to increase internal volume properly.

Because it gets wider, this is why the air flow around the box isn't simple as you can see.

I should have the best of both worlds correct?

A smaller cabin to pressurize and a loading area on top of that.

Box would be 9.0cuft tuned to 40hz using 2 Original AQ HD315s with 154sqin of port and 4,400w of power.

how about a sketchup or a model of some sort... its kind of hard to visualize sometime

[shizzzon 461]

i cant, i've already tried. It has to be a 3d design to understand.

[burton907 0]

how about some pics?

aka

DO IT!!!! (with pics!!)

[sound=vibration 34]

i cant, i've already tried. It has to be a 3d design to understand.

sketchup is 3d

[burton907 0]

well if we were anywhere near eachother i could draft it up for you very easily on AutoCad.

but seeing as i can't visualize waht your saying very well, i am no use righ tnow.

[burton907 0]

p.s. sketchup is free, from google. or atleast it was last i knew.

and it's pretty easy to use, as long as your somewhat computer literate. i'm sure you could learn it just find and have it do what you need.

[KU40 173]

Maybe make a couple of 2d sketches to show the contraption at different angles, then we can piece it together in 3d in our heads?

I'll just say to make sure that you allow enough airflow around the enclosure for the subs so that the air tunnels don't act as a second port. Plus you don't want one of those situations like some people run into who use too big of a box facing backwards in the trunk, the bass just gets stuck behind the enclosure and isn't as loud as it could be if facing forward. That back wall will also have to be VERY solid, because it will try to dissipate a lot of the energy as vibrations if it can.

Good luck though.

[Dangerous10k 0]

You should make it a Sixth Order bandpass

[shizzzon 461]

Yea, i know the wall needs to be braced very good!

It will be all-threaded along with the speaker box, no worries.

I have autocad but never got far enough to do 3d.

I'll get sketchup and see what happens.

[shizzzon 461]

Here is estimate, almost drawn to scale pics of box design-

The wall in front of the box WILL BE filled all around with triple expanding foam.

also, if you notice how the side of this box matches the width of the wall... Well, it may in the car but the side of the box does not meet the side of the CAR! Remember that.

The car gets wider so the box doesnt fill the entire width of the car.

The car is actually over 48" wide inside and the bottom of this box is 44", the top is 33"

There would be 8" from the subs\port to the wall giving enough breathing room I would expect.

[KU40 173]

Just some food for thought if you haven't already- competitors build walls with the subs in front sealed off behind the baffle because it gives the subs less airspace to pressurize inside the cabin. Facing them towards the rear will make the subs have to pressurize that extra little air around the box and behind the subs. I understand your loading idea, essentially emulating a trunk that is louder with the subs facing the rear of the trunk. I hope it works, but I'm just giving you a possible reason why it may not so that you can cover all of the angles. I'm not trying to dash your dreams as I've never seen this done before so it would be interesting.

[shizzzon 461]

I know exactly what you are saying but facing forward is a bad idea as well because it eliminates the loading area.

Now, if a wall is built and sealed, then yes, it helps a lot but you must rely on the airspace left to pressurize the volume.

My understanding is i wont have a lot of volume anyway after the wall is sealed off and the box is installed as it is.

As a matter of fact, i would have almost the same amount of volume left even facing backwards sealed off.

the only volume extra i have is the volume where the air flows out of so it's basically better theory-wise. Loading area + low pressure volume

[dbjunior 0]

id drop the hight of the box angle the face for the subs and port and block off the sides put the port on bottom aswell making almost a horn/wedge loading setup less impact on the soundwaves and better flow toward the front

[shizzzon 461]

how low do you want me to drop the height?

At the baffle i'm 0.5" away from hitting headliner but further back down the box i'm 1.5" away from hitting headliner.

I will say that by decreasing internal volume like this means that i will need to extend the depth meaning the box will be closer than 8" from the wall.

Since you gave some new idea to the design, how close to this wall before you think i would start choking?