How do i build a 12b/oct high-pass eq filter for a vented box

[cancerkazoo]

Fx : 28 hz
Qx : 2

where can i get a circut to build this for my car audio sub project?

 

[paulb]

Use part of:
http://sound.westhost.com/project09.htm

 

[richie00boy]

That is the circuit, the component values need to be calculated. Try my high-pass filter designer program on my website in the utilities section. www.readresearch.co.uk note that you will need to keep fiddling F3 to arrive at your desired Fx (which is plain F on my program).

 

[cancerkazoo]

Ok, thanks. I haven't looked yet, but are any of there active. that is what i would like. I would think it would need to be, to boost the amps output.

Thanks
Steve

 

[richie00boy]

Passive would require inductors, rarely done these days.

 

[pinkmouse]

Passive would require inductors, rarely done these days.

Huge, heavy, expensive, lossy ones at that.