The Altec Lansing 617-8A Duplex loudspeaker system consists of a two-way coaxial loudspeaker and a dividing network with equalization. It features a 12 inch low frequency cone and a coaxially mounted T-50 high frequency compression driver. The dual magnet construction allows each speaker to be structurally, magnetically, electrically and mechanically independent of the other. The 617-8A utilizes a dual section crossover network, centered at 1500 Hz and providing 12 dB of attenuation for both low frequencies and high frequencies.
 
8.0 Ohms nominal impedance 
Multimeter readout 6.97 Ohms (9.24.2024)