We have Acoustic Research floor standing bi-amplification speakers that are in excellent functioning condition.
This speakers has been carefully cleaned and tested carefully before putting for sale. Here is some general information about the speaker specifications:

3-way tower loudspeakers with bi-wireable side-firing woofer.
Dimensions(HxWxD): 37″ x 9″ x 17″
W: 73lbs Each
Driver Complement: Plasma Transfered Diamond-Coated 1″ Titanium Dome Tweeter
Dual 5 1/4″ Magnesium/Aluminum Monocoque Mid-Range
10″ High Excursion Woofer
All transducers are magnetically shielded
Frequency Response: 35Hz-23KHz +/- 2dB
Sensitivity: 95dB @ 2.83 Volts / Meter
System Impedance: 8 Ohms Nominal