One of the best speakers in the world of any audiophile, found these about two week ago and after some restoration they are up and running ….. 
Features
Accurate smooth reproduction from 35 to 20,000 Hz, ±3dB
44 dB SPL at 30 feet with a 1-milliwat input
101 dB SPL at 10 feet at one-half rated power input
Mountable in vertical or horizontal orientation
Components:
15″ low frequency loudspeaker,
10″ midrange loudspeaker,
High frequency compression driver with horn/lens assembly and ultra-high frequency transducer
Balance conrols located behind the removable grille
Rear mounted switch for bi-amplification or full passive crossover
Oiled walnut or textured gray enclosure
Ultra-High Frequency Transducer
Overtones above 9000 Hz are reproduced by a compression driver and diffraction horn specifically designed for reproduction and dispersion of energy at the extreme high end of the audio spectrum. The compression driver consist of a 3-1/4 pound magnetic assembly energized by an Alnico V magnet. The 1,75 inch edgewound aluminum ribbon voice coil, suspended within a field having a flux density of 16,500 gauss is affixed to a heat resistant support bonded to a ring diaphragm pneumatically formed of .0022 inch thick aluminum foil. Output from the diaphragm is directed through the integral diffraction horn, which produces the unit’s wide high frequency dispersion pattern.
Horn/Lens Assembly
Output from the high frequency compression driver is distributed through a controlled pattern by the horn/lens assembly. The horn is formed of a rigid casting to eliminate spurious resonance. The exponential taper rate of the horn controls the expansion of the wavefront providing proper acoustic loading of the driver diaphragm and determines the vertical dispersion pattern of the assembly. The acoustic lens functions in a manner analogous to a divergent optical lens. Its 11 plates set at a precise angle to the enclosure baffle panel, provide controlled propagation of high frequency acoustic energy in the horizontal plane.
Midrange Loudspeaker
The smooth performance and instantaneous transient response of the 10-inch midrange loudspeaker is largely responsible for the outstanding instrumental clarity, vocal definition and dimensional accuracy of the system. Its closed magnetic assembly weighing 6-1/2 pounds, concentrates all the energy of an Alnico V magnet in the voice coil gap. The 3-inch edgewound copper ribbon voice coil is suspended within a powerful magnetic field having a flux density of 10,000 gauss. The integrally stiffened cone is terminated with an wxclusive JBL ring compliance that allows long excursion while maintaining linear travel.
Low Frequency Loudspeaker
The 15-inch low frequency loudspeaker is mounted in a ported enclosure having an internal volume of 5,5 cubic feet. The driver features extreme, solid low frequency reproduction with smooth response well past its crossover frequency. The unit is energized by a 13-pound magnetic assembly concentrates a magnetic field having a flux density of 12,000 gauss in the voice coil is hand wound on a heat resistant support. The support is affixed to a rigid cone having optimum mass density and rigidity for exceptional transient response and maximum efficiency with the bandwidth of the driver.
laaudiophile 