Folded Motion Tweeter: MartinLogan's Folded Motion Tweeter helps give
the Motion 4 bookshelf loudspeaker its natural, realistic high frequency sound. Lightning fast
transient response, combined with a large surface area (8x that of a typical 1"
dome tweeter) creates clear, dynamic, and precise sound. The 1" x 1.4" Folded
Motion Tweeter works by moving air (which creates sound) perpendicular to the
folded ridges of the diaphragm, similar to how an accordion works. This
extremely low mass diaphragm "squeezes" air and requires almost 90% less
excursion than the typical 1" dome tweeter, which drastically minimizes
distortion while providing a lightning fast response time. The increased surface
area also provides a wide, yet controlled sound dispersion to create a realistic
and carefully etched sound stage.
4" Paper Cone Woofer: The MartinLogan Motion 4 loudspeaker features a
4" paper cone woofer with a stamped steel basket housed in a non-resonant
asymmetrical chamber. The paper cone woofer uses a rigid structured dust cap to
reduce cone break-up and distortion. This 4" cone woofer provides rich, detailed
Precision Crossover: To seamlessly blend the audio output from the
high frequency driver (tweeter) and the midbass driver (woofer), the Motion 4
loudspeaker features a precision 2900Hz crossover utilizing custom air
core coil and low DCR steel laminate inductors, polyester film capacitors in
series, and low DF electrolytic capacitors in parallel.
Folded Reflex Port Technology: MartinLogan engineers were faced with a
daunting task, create a compact speaker with low-end bass reproduction found in
speakers much larger. After a myriad of prototypes, they created the Folded
Motion Cascading Bass Port. This brilliant solution allows a long tuned port,
which is folded over itself (think of a trombone's tuning arm) to be compacted
and squeezed into the Motion 4 bookshelf loudspeaker. The result is amazingly
detailed low bass that can play at high volumes with minimum distortion; all
thanks to the elegantly simple cascading fold that slows down and controls the
air motion of the bass waves. The Folded Motion Cascading Bass Port exits the
rear-panel of the speaker cabinet.
Curved High-Gloss Black Cabinet: Complementing the Motion 4
loudspeaker's sonic accuracy is its elegant, yet understated styling. A
high-gloss, piano black finish and subtle curves, along with MartinLogan's
signature perforated grille, give the Motion 4 speaker an elegant and timeless
look that will blend into almost any decor.
Spring-Post Connectors: The MartinLogan Motion 4 speaker features two
spring-post connectors to attach your speaker wire. The spring-posts will accept
bare wire (16- to 10-gauge), pin-connectors, and banana plugs (single only). The
rubber caps on the spring-post connectors must be removed to use banana plugs.
Versatile Mounting Options: The MartinLogan Motion 4 bookshelf
loudspeaker can simply be placed on a table-top, stand, shelf, or other flat
surface. Four self-adhesive rubber feet are included for safe and secure
placement. Using the included keyhole-slot bracket, you can wall-mount the
speaker at two different angles. This means you can point sound directly toward
the desired listening area for high or low wall mounting applications. In
addition the Motion 4 is fitted with a 1/4"-20 threaded insert which allows you
to hang the speaker on the wall using optional articulating wall-mount brackets
- If the Motion 4 is being mounted at approximately ear-level, the speaker
should be oriented with the tweeter at the top. This will disperse sound
directly towards the desired listening area.
- If the Motion 4 is be mounted above ear-level, the speaker should be
oriented with the tweeter at the bottom. This will disperse the sound down
at a 20° angle towards the listening area.
Note: The MartinLogan logo badge on
the Motion 4's grille can be re-position based on how you have the speaker
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