Martin Logan describes both types of speakers as:
Impression ESL 11A The Immediacy of Exceptional Audio
The Impression ESL 11A is part of the Masterpiece Series. It features a dual 8-inch woofer system, with ARC-honed performance, for a perfectly blended low-frequency response. The groundbreaking integration of this woofer array and MartinLogan’s signature 11-inch wide XStat CLS transducer, coupled with a powerful dual amplifier section, delivers an expressive and dynamic audio experience. It's an experience of pure audio pleasure.
The Ultimate Center Channel Loudspeaker
This ambitious new center channel blurs the line between performance and reality by combining the unflinching accuracy of a 34-inch wide XStat™ CLS™ electrostatic transducer with the detailed imaging capability of dual Folded Motion XT tweeters. Additionally, four laser-engineered 6.5-inch aluminum cone woofers, driven by 250 watts of clean amplification with on-board Anthem Room Correction (ARC) technology, anchor the image to your screen and deliver massive cinematic impact.
We ordered the speakers in Deep Sea blue. Our commitment to that color became apparent when we had Sherwin Williams match it and we painted the walls the same. Jaclyn (my Wife) also painted the ceiling black again. She has become quite the expert little painter! Pics below of her work...
Actual specs are below but what I can tell you from our experiences the better the sound the more likely you are to have the ultimate movie immersion! The center channel has always been the single most important speaker during a movie. It is said that about 80% of the soundtrack comes out of it. Never skimp on it! And having terrific fronts to go along with it make it that much better. I have never used the term "life changing" to describe a piece of Audio Video equipment. The Illusion and Impressions have done just that in our home theater.
Specifications for the ILLUSION:
Frequency Response
45–23,000 Hz ±3dB
Horizontal Dispersion
30°
High Frequency Transducer
Two 1.25" x 2.4" (3.2cm x 6.1cm) Folded Motion XT Transducers with 4.5" x 2.75" (11.4cm x 7cm) diaphragm.
Mid Frequency Transducer
Patented CLS™ XStat™ electrostatic transducer
» Panel Dimensions
8" × 34.5" (20.3 × 87.6cm)
» Radiating Area
276 in2 (1,778 cm2)
Low Frequency Transducer
Four 6.5" (16.5cm) cast basket, high excursion, rigid aluminum cone with extended throw drive assembly, non-resonance asymmetrical chamber format.
Room Correction (Bass Section)
Anthem Room Correction (ARC) Ready (Sold Separately)
Amplifier
1x 250 watts/channel (4 ohms), 500 watts peak
Sensitivity
90 dB/2.83 volts/meter
Impedance
6 Ohms . Compatible with 4, 6, or 8 Ohm rated amplifiers.
Recommended Amplifier Power
20‒600 watts per channel
Crossover Frequency
500, 2000 Hz
Components
Custom-wound audio transformer, air core coils, polypro- pylene capacitors. 24-bit DSP based preamplifier (used with woofer amplifier).
Audio Controls
Bass: ±10dB under 75Hz
Mid-Bass: –2dB, 0dB, +2dB
ARC Room EQ: On, Off
Signal Inputs
WBT-0703Cu nextgen™ 5-way binding posts feature a filigree signal conductor made from gold plated, nickel free, non- ferromagnetic, pure copper for high conductivity and fully insulated. Free from eddy current effects.
Inputs
AC Power, RJ45 (for ARC), mini USB (for ARC)
Power Draw
Max: 300W per channel Standby: <1W per channel
Weight
90 lbs. (40.9 kg)
Dimensions
23.75" × 32.35" × 23.1"
(60.3cm × 82.2cm × 58.6cm)
Specifications for the IMPRESSIONS:
Frequency Response
29–23,000 Hz ±3dB
Horizontal Dispersion
30°
Vertical Dispersion
44" (112cm) line source
High Frequency Transducer
XStat™ CLS™ electrostatic transducer
» Panel Dimensions
44" × 11" (112 × 28cm)
» Radiating Area
484 in2 (3,136 cm2)
Low Frequency Transducer
Two 8” (20.3 cm) cast basket, high excursion, rigid aluminium cone and extended throw drive assembly, non-resonance asymmetrical chamber format.
Room Correction (Bass Section)
Anthem Room Correction (ARC™) ready (Sold Separately)
Amplifier
Woofer: 2 x 275 watts/channel (4 ohms), 2 x 550 watts peak
Sensitivity
91 dB/2.83 volts/meter
Impedance
4 Ohms, 0.6 at 20kHz. Compatible with 4, 6, or 8 Ohm rated amplifiers.
Recommended Amplifier Power
20‒550 watts per channel
Crossover Frequency
300Hz
Components
Custom-wound audio transformer, air core coils, polypropylene capacitors. 24-bit DSP based preamplifier (used with woofer amplifier).
Audio Controls
Bass: ±10 dB under 75 Hz
Mid-Bass: –2 dB, 0 db, +2 db
ARC™ Room EQ: On, Off
Signal Inputs
WBT-0703Cu nextgen™ 5-way binding posts feature a filigree signal conductor made from gold plated, nickel free, non- ferromagnetic, pure copper for high conductivity and fully insulated. Free from eddy current effects.
Inputs
AC Power, RJ45 (for ARC), mini USB (for ARC)
Power Draw
Idle: < 1W/channel
Max: 500W/channel
Weight
90 lbs. (40.9 kg)
Dimensions
60.75" × 11.9" × 27.4"
(154.3cm × 30.2cm × 69.6cm)
Sony VPL-VW5000ES, McIntosh MX160, McIntosh MC205, McIntosh MC207, DirecTV 4K, Oppo UDP-203, Panasonic DMP-UB900 4K Ultra Blu-ray, Darblet DVP 5000S, Samsung UBD-K8500 4K Ultra Blu-ray player, Zigen DA14-UHD HDMI distribution amplifier/splitter, Monster Power HTS 5100, Oppo 103D Blu ray, Value View 3D glasses, Antec Component Coolers, Stewart Studiotek 100 Screen, Speakers: MARTIN LOGAN ILLUSION, IMPRESSIONS (Left and Right), VANQUISH (HEIGHTS & ATMOS & T), AXIS (Backs), Subwoofers- Martin Logan BalancedForce 212 X 2, Dayton APA150 Sub AMP x 2, 8 Aura Pro Bass Shakers, 8 Black Seatcraft Venetian Home Theater Chairs (with Raffel Integrated Lighted Cup Holders), Remote: Harmony 1100, iPad Mini. Cables: Monster Black Platinum HDMI cables top to bottom. And two 35 foot Monster Black Platinum HDMI cables.