The History of the Transmission Line Speaker

This mini-series of episodes explores the transmission line loudspeaker. It represents one of audio engineering’s most fascinating attempts to solve a fundamental acoustic problem. Engineers must produce deep, uncoloured low-frequency sound from an enclosure without allowing the rear wave of the loudspeaker driver to interfere with the front wave.  

This topic holds personal interest for me because I recently purchased a pair of PMC Prophecy 5 loudspeakers. The transmission line serves as a trademark design for PMC across both domestic hi-fi and professional audio.

This second episode is the second in the series, we will look at the transmission line loudspeaker in detail. We will explore its historical development and examine the challenges that modern designers face. In next week’s episode, I will reflect on how the PMC Prophecy 5 speakers sound in my own home system before we prompt a debate about transmission line merits. 

This episode features Celtic folk songs from Ireland, Wales and Scotland using traditional words set to music arranged by the Hi-Fi Hobbyist with Mureka AI software. We hope that you enjoy these episodes!