Electrostatic Technology (How it Works):
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 Theos is a hybrid electrostatic loudspeaker
that features a XStat CLS electrostatic transducer panel, an optimized Vojtko
crossover, and a passive 8" woofer. 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 (425Hz) ensures a
seamless transition between the two sound reproduction philosophies. As a
result, this speaker offers the best performance for high, mid, and low
XStat CLS Transducer: The MartinLogan Theos 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 CLS, MicroPerf, Generation 2 Diaphragms,
ClearSpars, Vacuum Bonding, and AirFrame technology. 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.
- 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 Theos 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
- AirFrame Technology: The XStat CLS panel is secured to
speaker cabinet using MartinLogan's AirFrame technology. The AirFrame,
manufactured from aerospace-grade billet and extruded aluminum alloy, make
the panel extremely rigid while maximizing playable surface area and dipole
sound radiation. At the same time, it provides electrical and acoustical
isolation, minimizing intermodulation distortion caused by vibration and
resonance. Overall, AirFrame technology enhances imaging, low-level sonic detail,
accuracy, and efficiency.
Controlled Dispersion Sound Radiation: A key attribute of the
MartinLogan Theos is its naturally dipolar radiation pattern. A true dipole, the
Theos 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 Theos' 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
425Hz, because they are not needed. The Theos consists of a single, seamless
electrostatic membrane reproducing all frequencies above 425 Hz 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.
Passive 8" Woofer w/ Ported Cabinet: The MartinLogan Theos employs a
passive 8" high-excursion aluminum woofer w/ butyl rubber surround, a 425Hz
low-pass crossover, a
non-resonant composite/real-wood veneer cabinet, and an ultra-low turbulence
down-firing bass port to generate unyielding, detailed bass down to 43Hz. The MartinLogan Theos is available in a black ash or gloss back finish.
Note: When you first begin to play the Theos speaker, it will
sound a bit bass shy. This is due to the high-quality, long-life components
used in the passive woofer. The custom-made woofer requires approximately 72
hours of break-in at 90 dB (moderate listening levels) before any critical
listening. The break-in requirements of the crossover components (and, to a
lesser degree, the stator) are equivalent.
Advanced Vojtko Filtering: Proprietary Vojtko filtering
technology is utilized to transition between the Theos' electrostatic transducer
and passive 8" woofer. This audiophile quality
network is carefully hand-built using precision point-to-point wiring,
polypropylene capacitors, massive air-core coils, and a custom wound E-I core
transformer; flawlessly preserving micro-acoustic subtleties while effortlessly
handling the broadest range of dynamics contained within even the most demanding
Bi-Wirable Binding Post: The Theos 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 Theos, 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 Theos 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 Theos speaker features a signal
sensing circuit which will switch the Theos 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.
- Input: AC 100-240V~50/60Hz,
- Output: DC 15V, 0.4A
Applications: The MartinLogan Theos floor-standing speakers can be
used as stereo speakers or home theater front/surround speakers. The Theos
speakers are ideal for medium and small rooms.
Placement: The Theos speaker should be placed approximately 2' to 3'
from the front wall (the wall in front of the listening position) and about 2'
from the side walls. Your sitting distance should be further than the distance
between the Theos 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.
Note: The front wall surface ideally should be one long wall
without any doors, windows, or other openings. If you have openings, the
reflection and bass characteristics from each channel can be different.
Interchangeable Feet: The MartinLogan Theos floor-standing loudspeaker
includes four pre-installed rubber feet for tile and hardwood floors. You can
replace the pre-installed rubber feet with four metal spiked feet for carpeted
flooring. Both the rubber and spiked feet are threaded so they can be adjusted
to non-level floors.