MartinLogan Masterpiece Classic ESL 9 Matched pair of floor-standing speakers (Dark Cherry)

Features

Electrostatic Technology (How it Works): Where traditional loudspeaker technology incorporate cones, domes, diaphragms, and ribbons that are moved with magnetism, electrostatic loudspeakers employ charged electrons attracting and repelling each other. An electrostatic transducer consists of three pieces; stators, the diaphragm, and spacers. The diaphragm is what actually moves to excite the air and create music. The stator's job is to remain stationary and to provide a reference point for the moving diaphragm. The spacers provide the diaphragm with a fixed distance in which to move between the stators. As your amplifier sends music signals to an electrostatic speaker, these signals are changed into two high-voltage signals that are equal in strength but opposite in polarity. These high voltage signals are then applied to the stators. The resulting electrostatic field, created by the opposing high voltage on the stators, works simultaneously with and against the diaphragm, consequently moving it back and forth, producing music. This technique is known as push-pull operation and is a major contributor to the sonic purity of the electrostatic concept due to its exceptional linearity and low distortion.

Hybrid Electrostatic Speaker: The MartinLogan Classic ESL 9 is a hybrid electrostatic loudspeaker that features a XStat CLS electrostatic transducer panel, an optimized Vojtko crossover, and two passive 8" woofers. Electrostatic panels are perfect for reproducing high, midrange, and midbass frequencies. However, both the size and the power requirements of deep bass frequencies are best served by traditional cone woofers. A phase and amplitude optimized Vojtko crossover (380Hz) ensures a seamless transition between the two sound reproduction philosophies. As a result, this speaker offers the best performance for high, mid, and low frequencies.

• Controlled Dispersion Sound Radiation: A key attribute of the Classic ESL 9 is its naturally dipolar radiation pattern. A true dipole, the Classic ESL 9 radiates sound with equal intensity from the front and back of its diaphragm, but the outputs are in opposite phase. As a result, sound waves rippling out toward the sides meet at the speaker's edge and cancel. That and the relatively large size of the Classic ESL 9's electrostatic panel cause output at the sides to be very low relative to that of a conventional loudspeaker, which in turn minimizes side-wall reflections that tend to muddle sonic detail and stereo imaging. While the reduction in output to the sides contributes to the astonishing clarity, the energy reflected off the wall behind the speaker opens up and deepens the sound.
• Full-Range Operation: Another significant advantage of MartinLogan's exclusive electrostatic transducer technology is that no crossover networks are used above 500Hz, because they are not needed. The Classic ESL 9 consists of a single, seamless electrostatic membrane reproducing all frequencies above 500Hz simultaneously. This eliminates the crossover phase aberrations that are associated with traditional tweeter, midrange, and woofer systems. The result is a dramatic improvement in imaging and staging performance.

XStat CLS Transducer:  The MartinLogan Classic ESL 9 features a 9.2" (w) x 44" (h) XStat CLS Transducer. This new XStat transducer builds upon the legacy of MartinLogan's electrostatic heritage with the incorporation of a myriad of technology and design innovations including AirFrame Blade Technology, CLS, MicroPerf, Generation 2 Diaphragms, ClearSpars, and Vacuum Bonding.. Through rigorous testing, this curvilinear electrostatic panel has proven itself to be one of the most durable and reliable transducers available today. Fabricated from a custom tool punched high-grade steel, the patented panel is then coated with a special polymer that is applied via a proprietary electrostatic bonding process. This panel assembly houses a membrane just 0.0005" thick. Ruggedly constructed and insulated, the panel is rated to easily handle 20 to 400 watts of power.

• AirFrame Blade Technology: Classic ESL 9 XStat panels are joined to their speaker cabinets using MartinLogan's redesigned AirFrame Blade construction, precision manufactured from an aerospace-grade extruded aluminum alloy. This material, and this exclusive manufacturing process, makes the panels extremely rigid. It never obstructs playable surface area or interferes with the panel’s dipole sound radiation pattern. It also provides electrical and acoustical isolation, minimizing intermodulation distortion caused by vibration and resonance. The AirFram Blade design enhances imaging, low-level sonic detail, accuracy, and speaker efficiency.
• CLS (Curvilinear Line Source): MartinLogan engineers discovered a simple solution to achieve a smooth pattern of dispersion from a smaller electrostatic transducer without degrading sound quality. By curving the horizontal plane of the electrostatic transducer, a controlled 30° horizontal dispersion pattern could be achieved, yet the purity of the almost massless electrostatic diaphragm remained uncompromised.
• Generation 2 Diaphragm: The diaphragm used in the ElectroMotion ESL 9 XStat transducer employs an extremely sophisticated conductive coating applied to the polymer surface at an atomic level using a plasma bonding process. A proprietary compound is driven into the surface of the polymer film in an oxygen free argon chamber. This process allows extremely uniform surface resistivity characteristics, an optically transparent surface, and a nearly massless diaphragm. This uniform surface resistivity controls the electrostatic charge on the diaphragm surface and regulates its movement.
• MicroPerf Stator: Although stators are the elements of an electrostatic driver that are supposed to stand still, they carry the audio signals that do the work of propelling the diaphragm back and forth to move air and produce sound. Because the stators sandwich the diaphragm between them, they must be perforated to allow sound to pass through. Yet they must also be rigid enough to remain absolutely stationary despite the strong electrostatic forces pushing and pulling at them during operation. MartinLogan's MicroPerf design optimizes this tradeoff by reducing the size of the individual holes and using many more of them than in a traditional electrostatic panel. MicroPerf almost doubles effective diaphragm radiating area without compromising structural integrity. The resulting increase in output capability and efficiency allows the XStat CLS panel to be made much smaller without sacrificing performance and lets you enjoy a substantial leap in bandwidth and dynamics.
• Vacuum Bonding + ClearSpar Spacers: To achieve the power, precision, and strength of the XStat transducer, two insulated high-purity carbon steel stators along with a proprietary plasma bonded diaphragm and ClearSpar spacers are fused into a curved geometry with an aerospace adhesive whose strength exceeds that of welding. MartinLogan's proprietary Vacuum Bonding process guarantees uniform diaphragm tensioning and extremely precise construction tolerances, resulting in precision, linearity and efficiency.

Dual 8" Woofers w/ Ported Cabinet: The MartinLogan Classic ESL 9 uses two 8" laser-engineered. low-distortion aluminum cone woofers balanced in an opposing array; one forward- and one rear-firing. This design greatly reduces cabinet vibrations inherent in same-direction woofer positioning, specifically in the 34Hz to 100Hz range for uniform frequency response resulting in realistic bass effects you can feel. Roll-off characteristics for this opposing woofer array are further optimized for realistic coherent bass response. In addition, MartinLogan tuned the rear-firing woofer to minimize near-wall interactions, perfectly complementing the dipole nature of the electrostatic panel. Bass performance from this configuration is accurate, musical and utterly lifelike. The efficient, cast basket woofer design improves cone suspension and the magnetic flux field, maximizing response time, to produce truly profound bass output (down to 34Hz) with low distortion.

ForceForward Bass Reflex Cabinet: The depth of Classic ESL 9 speaker cabinet was carefully chosen to maximize benefits of advanced bass technologies, providing a level of low-frequency precision that is truly unique. With ForceForward bass technology, the farther apart the woofers are from each other the lower in frequency its beneficial effects extend. MartinLogan's ForceForward technology has solved a problem (found in nearly all speakers) where low bass frequency soundwaves reflect off the wall behind the speakers and interact with the waves traveling towards the listener. These interactions create non-linearity in those frequencies as they arrive at your ears and bass information suffers from both cancelations and excessiveness that is not accurate to the original sound. By selectively adjusting phasing of output from the opposing woofers, the Classic ESL 9 speaker eliminates problematic bass energy from behind the speakers. A flared, ultra-low turbulence rear-firing slotted bass port is also integral to the design of the enclosure, providing an extra layer of rigid internal bracing and increasing deep bass output with no added port noise.

Proprietary Vojtko Filtering: To seamlessly blend audio output from the high- and mid-frequency electrostatic panel to the low-frequency woofers the Classic ESL9 features a proprietary Vojtko topology filter utilizing custom air core coil and low DCR steel laminate inductors, polyester film capacitors in series, and low DF electrolytic capacitors in parallel.

Bi-Wirable Binding Post: The Classic ESL 9 features bi-wirable binding posts and provide the ultimate level of flexibility for connection and setup. MartinLogan's proprietary tool-less binding posts simplify cable connection and management. Two sets are supplied; one connected to the electrostatic panel and the other feeding the woofer. You can choose to bi-amp the ESL X, or use jumper clips between the binding post sets for a single wire-connection. The binding posts will accept bare wire (16- to 8-gauge), pin-connectors, spade-connectors, and banana plugs (single only).

Low-Voltage DC Power Supply: The Classic ESL 9 speaker uses an external low-voltage power supply to energize its electrostatic panel. The included power supply firmly inserts into the "DC Power In" receptacle on the rear-panel of the speaker and then to an AC wall outlet. The Classic ESL 9 speaker features a signal sensing circuit which will switch the Classic ESL 9 off after a few minutes of no music signal, and requires less than two seconds to recharge the panels when a music signal is present.

Applications: The MartinLogan Classic ESL 9 floor-standing loudspeakers can be used as stereo speakers or home theater front/surround speakers. The Classic ESL 9 speakers are ideal for medium and large rooms.

Placement: The depth of Classic ESL 9 speaker cabinet lends itself to providing the electrostatic panel with adequate distance from the wall, guaranteeing a richly detailed, three-dimensional soundstage. The Classic ESL 9 speaker can be positioned closer to the wall than previous generations of MartinLogan speakers. As a rule of thumb MartinLogan recommends placing the rear of the speaker cabinet no closer to the wall than the diameter of its woofer (which in this case is 8"). Your sitting distance should be further than the distance between the Classic ESL 9 speakers themselves. This will allow you to attain good center imaging and stage width. Generally, it is found that the ideal listening position is with the speakers slightly toed-in so that you are listening to the inner third of the curved transducer section. 

Interchangeable Feet: The MartinLogan Classic ESL 9 floor-standing loudspeaker includes four pre-installed rubber feet for tile and hardwood floors. You can remove the rubber feet and install metal spike feet for carpeted flooring. The spike feet are threaded into the base of the speaker and can be adjusted to non-level surfaces.