A Three Way ?
/THE LEGENDARY KLIPSCHORN® - A fully horn-loaded loudspeaker of superior design and exquisite craftsmanship by Jim Hunter and Matt Sommers. An excerpt from the book.
Back when it was first invented, a two-way (tweeter and woofer) Klipschorn with a frequency response up to 12Khz was generally adequate for the program material created up to that time. However, by the early 1950s, recording processes and playback technology had improved fidelity substantially, especially in high frequency detail, by using magnetic tape.
Due to the difficulty and expense of getting a mid-range driver to reach to the top end of the extended range now available with modern playback machines, the factory began converting Klipschorns to a three-way (tweeter, squawker, woofer) configuration in 1951.
The first three-way Klipschorn incorporated a Jensen RP203 tweeter. The University MID-T-4401 replaced the Jensen as the tweeter of choice later that year. It was not until mid-1952 that all units were finally converted to the three-way design still used today.