[Derockster]

Can someone explain to me what a B4 alignment is?

[*Scotty*]

These pdf docs help explain vented alignments. See links below
http://diyaudioprojects.com/Technical/Papers/Vented-Box-Loudspeaker-Systems-Part-I.pdf
http://diyaudioprojects.com/Technical/Papers/Vented-Box-Loudspeaker-Systems-Part-II.pdf
Scotty

[Davey]

Can someone explain to me what a B4 alignment is?

B4 is a vented box....."B"utterworth "4"th-order.  The Butterworth characteristic describes a maximally flat response with no peaking (Q=0.707), and the 4th-order describes the ultimate roll-off characteristic.  In this case 4th-order or 24db per octave.

There are literally thousands of online texts describing vented and sealed-box alignments.  You can Google this and find numerous excellent articles.

Dave.

[Derockster]

Thank you very much.

I am exploring building a sub for my horn system but I need it to play as high as 700/800 hertz.

[Speedskater]

Don't think sub, think woofer.