Frequency response -- 30 Hz - 40 kHz +/- 3 dB on axis (in room)
Peak SPL -- 105 dB (pair playing music at 4 m [13'] in mid-sized room -- 4.5 m x 7.3 m x 3.0 m (15' x 24' x 10')
Fully enclosed, not dipoles, makes placement easy
Listening area
Full spectrum 2 m wide @ 4 m (6.5' wide @ 13')
Very tight vertical dispersion and relatively narrow horizontal dispersion conserves recorded ambience, reduces interaction with the room, and sharpens the soundstage, yet is wide enough to avoid a headphone effect
Crossover -- 1st order @ 500 Hz -- far below the disturbance-sensitive hearing region of 1 kHz - 3 kHz; entire midrange and treble carried by the electrostatic elements; minimum phase operation through crossover region
Secondary partial crossover -- 1st order at 5 kHz -- limits upper treble from half width of ESL panel -- controls dispersion and flattens response without an electrical rolloff network
2.5.5 way, quasi-line configuration
Woofer mounted below ESL array; ESL panels employ half-split-response (1.5 way ESL), additional woofer in back covering deep bass only
Woofer radiation pattern mates well to ESL array
Excellent phase alignment for soundstage focus
Vertical image stability
Recorded image height is well presented, even above tops of speakers
Four DSP presets; standard are: very near wall; normal; far; and console
ESL panels
One panel in each speaker, mounted in a barometrically isolated sub-enclosure, 18 cm wide x 20 cm high [7"H x 8"W]
Protected by an integral barrier
260 square cm [40 square inch] forward radiating area per array
Introduces absolutely no midrange or treble coloration, and distortion is far below audibility
Will not lose its tension or degrade over time
1.5 way tweeter/mid design controls horizontal dispersion and eliminates electrical EQ network
Woofers
16.5 cm [6.5"], paper cone, extra low distortion, low inductance, high resolution, very long excursion driver with neodymium magnet structure
Operate far below their breakup frequencies and their Xmax for practically no cone coloration
Seamless acoustical integration with the ESL
Strong, accurate bass, not boomy dance club bass
Direct connection to amplifier creates maximal damping factor and thus maximizes cone control
Enclosure
Sealed (acoustic suspension) for best woofer transient response, minimal group delay, and best integration with electrostatic panel
High mass, 25 mm [1”] thick, well damped, well braced walls for negligible enclosure radiation
Baffle step (diffraction interference) is reduced with front edge scoops, which are also visually interesting
Amplifiers
Input
True balanced XLR
Operates well, however, with RCA adapter (supplied upon request).
Input impedance: 10 kΩ balanced to ground
Maximum gain: 32 dB (x40 voltage gain)
S/N ratio: >113 dBA (20 Hz – 20 kHz, A weighted)
Damping factor: >1000 (20 – 1000 Hz)
Distortion: < 0.0005% (THD, DIM, SMPTE)
Mains power – <150 Watts playing music at full gain (assuming 12 dB crest factor, 6 Ω average impedance), <1A on 120V mains – 95% efficiency typical, starting from 1/8th maximum power -- very green
Works from any mains worldwide without adjustment
Built-in surge protection
IEC cord inlet with power switch -- uses standard power cords worldwide
Diaphragm polarization supply
Mains power -- 0.1 Watts to 1.0 Watts, depending on mains voltage -- very green
Works from any mains worldwide without adjustment
Built-in surge protection
IEC cord inlet with power switch -- uses standard power cords worldwide
No transformer or oscillator -- high reliability, and no radiated or conducted noise to affect your other components
Weight -- 16 kg [35 lbs] each
Dimensions: 43 cm high x 20 cm wide x 33 cm deep [17" H x 8" W x 13" D]
Heirloom quality materials and finishes used throughout for lifetime operation, yet all are recyclable
Designed, engineered and made in the USA
Warranty -- 5 years on all components against defects in materials and manufacturing
Modular construction and simple disassembly for straightforward repairs, even in the field
Miscellaneous
10 mm [3/8"] thick, wool felt to kill internal edge diffraction
Appearance options available (custom finishes/paints, custom wood veneers)
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