Quantum 3

Introduced: 1977
Dimensions:  102 x 45 x 33 cm
Bass: 1 x 30 cm
Mids: 1 x 10 cm midbass coupler, 1 x 3,8 cm
Highs: 2 x EMIT
Suggested for amplifiers with: 60-250 Watts per channel
Frequency range: 28 Hz - 32 kHz
Crossover frequencies: 200 Hz, 600 Hz, 4000 Hz
Suggested price (pair):  1050 $

A technical sheet with crossover schematics can be seen here.

You can view a brochure of the Quantum 3 here.
page 1, page 2