The tweeter was the real innovation. A Winslow Burhoe inverted dome design. That tweeter (also found in the EPI 100) inspired a young Frenchman - Jacques Mahul – who was an engineer at high-volume driver manufacturer Audax in Tours, France. He left in 1979 & started building speakers in the backroom of his father's tooling factory in Saint-Etienne, France. Mahul's company is Focal (he just retired as CEO in April but he is still Chairman of the Board of Focal & Co.- a new company that includes the English amplifier company Naim). I have been selling Focal since 1993 & all use an inverted dome tweeter - which offers wider dispersion & much greater mechanical integrity for lower distortion & higher sensitivity than the more conventional positive dome.
But . . . that Winslow tweeter – with its plastic diaphragm - only had a high frequency extension to ~ 15KHz (that’s 5kHz LESS than the 20kHz limit of normal human hearing btw). Focal's current Beryllium inverted dome tweeters go up flat to >40kHz.
End of lesson.
Here is the inverted dome on my computer speakers (
) . . . Focal Solo 6 BE . . . from their professional division . . .
As for the speakers: a decent mid-70s polite New England sound, with no real bass extension. Not worth a big investment but a nice piece of history.
Ian