Building a transmission line for old 3 way floor speakers.

[shanesauce]

I am about to dive into this little project head first, my old 4 channel sony home stereo recently lost channel 3 for some reason so I am going to use it for a 2.0 setup on my computer. I have 2 KLH Audio floor speakers and I believe the model is 1230SB but not 100 percent on that.

I am aware these are not the greatest speaker or crossovers. But it consists of a 2 inch tweeter a 4 or so inch mid range and a 12 inch woofer. The cabinet seems to be tuned around 45-50hz or so.

If I were to build a transmission line @40hz for the woofer which may be getting about 20rms from my receiver, would there be a big difference in bass response? I mean the woofers kick but they just don't have any drop to them and the cabinet doesn't help that at all.

Port area would be about 90 square inches and the line would be around 85 inches if I'm not mistaken. So a 4' tall, 1.5' deep and 1' wide cabinet.

Any pointers or suggestions? I also have a pair of bookshelf speakers I could make a t-line for but I wasn't sure how the mid bass would interfere with the bass response.