how to build a transmission line


2004-10-19 4:29 pm
The first thing I do is pick out a speaker or speakers that I would like to be in a TL. I then get the T/S parameters for it. With the FS parameter I then apply this formula to find out how long the pipe is going to be;
(1128/Fs)/4 = 1/4 wave in feet
Feet x 12 = length in inchs.

Let's say the driver has an FS of 40 hz.

1128/40 = 28 28/4 = 7 x12 = 84.6 inches

I then apply this to MJK's worksheet and start entering the numbers.

I massage the numbers until I match the speaker (red line) with the infinite baffle (blue line)...

I then get some chart paper and design the box.

My latest creation;

and the front;

I haven't charted the frequency response so I can post it yet, but they sound great. Unbelievable bass out of the 2 - 5 " Dayton Classics;
They sounded so good I removed the 3/4 " Dayton Neo's and gave them a Seas tweeter (H1212) and crossed them over at 1400 hz.