PMC fact.8 signature loudspeaker

Back in the Dark Ages, loudspeaker design was commonly based on semi-enlightened experimentation, with new enclosure configurations appearing almost monthly in professional and consumer journals. One of those, published in Wireless World in October of 1965, was A.R. Bailey's transmission line, a long, selectively resistive, folded-and-sometimes-tapered tube that loaded the back of the (woofer) driver for low-bass reinforcement.