MartinLogan Motion 15i Bookshelf Speaker (Matte White)

Bookshelf speaker featuring a Folded Motion® tweeter and
5.25-inch aluminum cone woofer with a rear-firing bass port. Available in three
stylish finishes: gloss black, matte white, and red walnut.

Motion 15i Bookshelf Speakers

The high-performance Motion 15i bookshelf speaker features a
Folded Motion® tweeter, a 5.25-inch aluminum cone woofer with a rear-firing
bass port, and a proprietary Vojtko crossover network to deliver refined sound
with stunning dynamic range and jaw-dropping clarity. Motion 15i delivers the
classic broad soundstage of the Motion Series from a newly designed enclosure
enhanced by the slightest of modifications, including the drive-stabilizing
dust cap design and stiffened motor suspension. The speaker’s cabinet sports a
reinforced baffle and a fabric grille. Available in three stylish finishes:
gloss black, matte white, and red walnut.

Engineering, Without Compromises

What makes the Motion Series sound so amazing? MartinLogan’s
dedicated in-house engineering and design team started by utilizing and
refining the most advanced, compact technologies and combining them with
innovative engineering and time-honored cabinet construction techniques. The
result is an emotionally engaging sound that rivals (and most times trounces)
traditional loudspeakers of similar size and price. Our ‘no compromise’
philosophy gives Motion Series a unique sound you won’t find anywhere else.

Sound Inspired by Electrostatic Speakers

The success of the Motion Series is directly attributed to
its close relation to MartinLogan’s legendary ultra-high-end electrostatic
loudspeakers. The desire to transmute that level of performance into a more
traditional loudspeaker at a more affordable price drove the initial design
imperatives that created the Motion Series.

Folded Motion^® Tweeters

MartinLogan’s signature Folded Motion tweeter utilizes an
extremely low mass diaphragm that “squeezes” air, thus demanding
significantly less excursion than the typical 1-inch dome tweeter. Its folded
design allows for a much larger surface area (compared to that of a regular
1-inch dome tweeter), controlled dispersion characteristics, and vanishingly
low distortion. It’s a miracle of audio engineering that’s able to deliver much
of the high-frequency detail and speed of a large, dynamic electrostatic panel
in a small space. Folded Motion XT tweeters, advanced thin-film transducer
technology even further, with a 40% larger radiating surface and 80×30-degree
controlled dispersion. This tweak increases audible bandwidth without
sacrificing details and minimizes distortion to an unprecedented level while
increasing efficiency and the tweeter’s already lightning-fast response time.
The result—superior realism and alarming specificity is aurally astounding, and
only by MartinLogan.

Powerful Aluminum Cone Mid-Frequency and Bass Drivers

Custom built, low-distortion drivers pair high-power magnet
structures with aluminum cone diaphragms to deliver massive excursion and sound
output, preserve minute bass details, and maximize power handling capability,
all without a hint of distortion. A unique concave dust cap design reinforces
the strength and rigidity of the cone while reducing break up modes.

The use of aluminum for cones maximizes rigidity and strength
of the drivers without adding excessive weight. This, along with the
exceptional damping properties of aluminum, ensures the smooth, non-resonant
response necessary for seamless blending with high-resolution Folded Motion
tweeters. An added benefit of aluminum is its outstanding thermal conduction
capability which allows cones to serve as efficient heat sinks for voice coils.

To deliver accuracy in the critical midrange, mid-frequency
drivers feature a specially engineered “stiff” suspension. Stiffening
the suspension (the spider and surround) raises the driver’s resonant frequency
and optimizes its performance to achieve a natural roll-off and inherently
operate within an ideal range for a mid-frequency reproduction (as opposed to a
comparably sized woofer).

Proprietary Vojtko^™ Crossover Networks

Premium Motion Series speakers feature proprietary Vojtko
crossover networks using polypropylene and low-DF electrolytic capacitors,
custom-wound inductors, and thermal and current protection.

Vojtko crossovers are named after MartinLogan’s chief audio
technologist, Joe Vojtko. His unique approach to crossover design is as big of
a part of the “MartinLogan Sound” as are electrostatic and Folded
Motion thin-film driver technologies. A Vojtko crossover isn’t so much a set of
design requirements as it is a philosophy. Vojtko crossovers are designed in
such a way that all drivers are kept within their optimal frequency range and
balanced with one another. The drivers themselves are as much a part of a
Vojtko crossover as are capacitors and resistors. Before the design of any
crossover begins, drivers are carefully selected or designed to operate within
a very intentional frequency range and with precise and predictable performance
parameters. Vojtko crossovers are always built from high-quality parts, and
care is taken to avoid overly complex topologies—a straightforward objective
due to the careful selection of woofers and tweeters. The final (and most
critical) aspect of a Vojtko Crossover is that final voicing is conducted in a
space that is indicative of a real-world environment. This pragmatic approach
allows MartinLogan speakers to sound their best in real-world rooms.

Modern Design Featuring Luxurious Finishes

Discreetly hidden behind fabric wrapped magnetic grilles,
Folded Motion and aluminum cone drivers are held securely in place beneath
matte black trim that masks tweeter and woofer mounting hardware for a clean,
modern aesthetic. Solid cabinets, designed to eliminate fidelity robbing
vibrations, are constructed from 18mm (0.7-inch) MDF with 31mm (1.2-inch) thick
front baffles. Motion 60XTi and 50XTi feature additional internal bracing to
further reduce cabinet resonance.

MartinLogan’s premier Motion Series speakers are available
in three luxurious finishes and matching metallic trim—gloss black with black
grilles and gunmetal grey trim, matte white with silver grilles and silver
trim, and red walnut with black grilles and champagne colored trim.

Custom 5-Way Tool-less Binding Posts

Premium gold-plated 5-way tool-less binding posts assure a
stable connection while accommodating bare wire, banana plug, spade lug,
terminal pin, and (seldom used) alligator clip connections.

Specifications

Specifications are subject to change without notice

Frequency Response	60–25,000 Hz ±3dB
Recommended Amplifier Power	20—200 watts per channel
Horizontal Dispersion	80°
Vertical Dispersion	80°
Sensitivity	92 dB/2.83 volts/meter
Impedance	5 Ohms Compatible with 4, 6, or 8 Ohm rated amplifiers.
Crossover Frequency	2,700 Hz
High Frequency Transducer	1″ × 1.4″ (2.6cm × 3.6cm) Folded Motion Transducer with 5.25″ × 1.75″ (13.3cm × 4.4cm) diaphragm
Low Frequency Transducer	5.25” (13.3cm) aluminum cone with cast basket. Non-resonant asymmetrical chamber format. Rigid structured dust cap to reduce cone break-up modes.
Components	Custom air core coil and low DCR steel laminate inductors. Polypropylene film capacitors in series and low DF electrolytic capacitors in parallel. Overall system thermal/current protection.
Inputs	Custom 5-way tool-less binding posts
Weight	12 lbs. (5.4 kg)
Dimensions	11.4″ x 6.8″ x 9.5 “ (29cm x 17.3cm x 24cm)