Austrian loudspeaker manufacturer Trenner & Friedl has a thing for coaxial drivers. They're used in at least three of the company's eight loudspeaker models, including the diminutive Sun bookshelf speaker and the large floorstanding Taliesin. In these models, T&F eschew more conventional stacked drivers for a putatively time-aligned, wide-frequency range coaxial design.

"The crying rain like a trumpet sang
And asked for no applause."—Bob Dylan, "Lay Down Your Weary Tune"

I remember as a toddler sitting in the kitchen on a highchair, watching my mother smoke a cigarette, apply red lipstick, and tune a turquoise table radio from one news station to another. Between the strange, nattering voices, the radio emitted a sharp hissing sound. That's my first memory of human voices coming from a little box.

"Stirring the stew" is what I've heard it called when a company introduces a new version of a product every three or four years. When a new product is launched, sales generally rise rapidly to a maximum and then slowly decline. If the stew is stirred every few years, plotting the product's sales volume against time results in a sawtooth wave, without sales ever dropping close to zero.