The MartinLogan Classic ESL 9 are a passive design pair of ESL speakers with a 9.2" wide electrostatic transducer and dual 8 inch woofers.  These speakers produce a rich transparent sound. 

Price is for 2 speakers (1 pair)

• Frequency Response 34–23,000 Hz ±3dB
• Recommended Amplifier Power 20—400 watts per channel
• Horizontal Dispersion 30°
• Vertical Dispersion 44" (112cm) line source
• Sensitivity 90 dB/2.83 volts/meter
• Impedance 4 Ohms, 0.8 at 20kHz Compatible with 4, 6, or 8 Ohm rated amplifiers
• Crossover Frequency 380Hz
• High Frequency Transducer XStat™ CLS™ electrostatic transducer
• Panel Dimensions: 44" x 9.2" (112 x 23cm) » Radiating Area: 405 in² (2,576 cm² )
• Two 8” (20.3 cm) cast basket, high excursion, rigid aluminium cone woofers with extended throw drive assembly, non-resonance asymmetrical chamber format
• Custom-wound audio transformer, air core coils, low DCR steel laminate coils, polyester capacitors

Weight: 78 lbs. (35.4 kg)

Dimensions:  59.8" H x 10.4" W x 25.4" D

Warranty: 5 years parts and labour 

Reviews: 

The MartinLogan Classic ESL 9 Speakers: A Worthy Successor
"When I reviewed the MartinLogan Summits back in issue 13, their ability to deliver a major dynamic swing proved impressive. Finally there were some panels that could deliver enough oomph, providing a visceral enough experience to play rock music at a respectable level. The ESL 9 fully embodies this tradition, with a level of refinement that the earlier model did not have." —Jeff Dorgay, TONE Audio