4th order bandpass, need some assistance

[savagebee 10+ year member]

I dont need or really want plans, as this will be an incar build, but I need some help determining the sizes of each chamber + tuning between them

I have a 10 cube + wall tuned to 28(ish) right now, but Im bored and wanting to do another in car build here...

so, please help...

space isnt an issue, as I have well over 20 cubes available for this, and thats without stretching or fiberglass, so that shouldnt be an issue

this will be for 2 elemental designs 19ov.2s

and I will have 2500wrms on tap for this

Im wanting extremely good low end extension, spl is important to me (its a wall with 2 18"s after all) but I dont want the fart box, at all. Overt peaks are something I want to avoid, but I know they will be there with a bandpass design any way

the wall is in a 92 caprice wagon, and it extends to the back of the second row of seats, here is a pic to show the placement of it

thanks yall

here are the t/s specs

Qts: .369

Qes: .37

Qms: 7.5

Fs: 26 Hz

Re: 3.5

Vas: 228 L

Mms: 307 g

Bl: 22.1 T*m

SPL: 90.5 dB

Sd: 1200 cm^2

Xmax: 22 mm

Voice Coil: 62.5 mm

Magnet Width: 8.200"

Cutout Diameter: 16.375"

Mounting Depth: 9.625"

Weight: 42 lb

Total Height: 10.600"

Displacement: .10 ft^3

Outside Diameter: 18.375"

Click to read more...

 

[BrianChia 10+ year member]

What is your response goal? SPL peak or flat extension? Also what car is it going in and how far up are you going to cut the wall in the cabin.

 

[savagebee 10+ year member]

What is your response goal? SPL peak or flat extension? Also what car is it going in and how far up are you going to cut the wall in the cabin.

im sorry, I really should have put this in there...

Im editing the o.p.

Im wanting extremely good low end extension, spl is important to me (its a wall with 2 18"s after all) but I dont want the fart box, at all. Overt peaks are something I want to avoid, but I know they will be there with a bandpass design any way

the wall is in a 92 caprice wagon, and it extends to the back of the second row of seats, Ill find a picture to demonstrate that

 

[savagebee 10+ year member]

my current wall was a ***** wall build, i built it outside of the car, so meh..

Im wanting to have something serious here, for this build I mean, Im getting to itch to go extreme again, and this sounds like fun to me

Ive already got to take this wall out, as Im upgrading my charging system, so I figured why not completely trash it and blow a few hundred on wood, right?

 

[savagebee 10+ year member]

also, feel free to mock my subs if that makes it okay to give me some pointers

 

[BrianChia 10+ year member]

Desired crossover frequency?

 

[savagebee 10+ year member]

Desired crossover frequency?

top end @ 80 hertz max, anything around 70 is fine though, I have an undefeatable ssf @ 15, but I prefer to not use it at all, like I said, lfe is the important part of this for me

 

[IamDeMan 5,000+ posts]

also, feel free to mock my subs if that makes it okay to give me some pointers

BWAHAHA I mock the E duhs!

You said to //content.invisioncic.com/y282845/emoticons/hide.gif.2d479cfd917eedfe201353b91522ceab.gif

 

[savagebee 10+ year member]

BWAHAHA I mock the E duhs!
You said to //content.invisioncic.com/y282845/emoticons/hide.gif.2d479cfd917eedfe201353b91522ceab.gif

:sad:

ver it now:

 

[IamDeMan 5,000+ posts]

This is gonna be huge //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

Where is 80 when you need him?

 

[IamDeMan 5,000+ posts]

I wish I could help determine the air spaces but I have never designed one. Did you throw these is BBP to see what it says?

 

[savagebee 10+ year member]

This is gonna be huge //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif
Where is 80 when you need him?

Im okay with that, with the pregnancy advancing, and my wife not working as much after this month, I need some new projects for getting into the shop, and the coffee table Im doing wont take long

I like huge //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

hopefully 80 will make an appearance

 

[savagebee 10+ year member]

I wish I could help determine the air spaces but I have never designed one. Did you throw these is BBP to see what it says?

no, Ive had a hell of time trying to get good results with WinISD, and I dont have BBP

 

[BrianChia 10+ year member]

Rear chamber roughly 12 cf, front chamber roughly 7 cf, port tuned 60-65hz. This should yield a fairly flat response from 20hz-70hz. The simulated response curve is actually almost beautifully flat.

 

[savagebee 10+ year member]

Rear chamber roughly 12 cf, front chamber roughly 7 cf, port tuned 60-65hz. This should yield a fairly flat response from 20hz-70hz. The simulated response curve is actually almost beautifully flat.

wowza

awesome

Ill play with this, and post some sketchup suff up

how do you think the output would match up with my conventional ported box?

(Wild *** guesses perfectly acceptable)