What can anyone say about Quarter Wavelength transmission line enclosure design ?

Bingo! Exactamundo! Pre-internet days!

That, Glass Audio and Audio Amateur, were my favorite rags(back in the day).   Inspiring!

Ohm Walsh speakers use a transmission line. The bass has real impact and slam. Nothing polite about the bass it produces.

Salk Sound also uses TL. Never heard them but the bass measurements are impressive for the speaker sizes.

Quarter wave is popular in the DIY community. Tabaq is a popular DIY quarter wave design. A company named Kvart & Bolge made a really cool and low priced commercial speaker from this design called the Sound Sommelier. I have a pair and they really disappear.  

Acoustic Zen loudspeakers utilize the transmission line design. They sound phenomenal!!! 

I built the electrostatic panels too, rodman. Just the way Sanders described. They sure looked like they would work! But being a starving college student it took me a while figuring out how to find and buy everything for the power supply to make them work. In the meantime I for some unfathomable reason decided to remove the woofers from the TLs.

Now if you ever do this be sure to use a cap or something to cover the speaker mounting bolts. Because the whole thing is stuffed with dacron. If you don't cap the bolts then when you go to remove the bolt the dacron gets wrapped around it so tight you're never getting that bolt out without destroying the cabinet, or the driver, or both.

And that will be the end of your glorious Speaker Builder Electrostatic TL project. Sigh.