MartinLogan Depth subwoofer - Manual (Page 17)

Resulting from an equal and opposite reaction to the cone's
movement, strong bass causes traditional subwoofer enclo-
sures to generate acoustic vibrations. You feel this by touching
the cabinet. Although the "physics" of this phenomenon
actually cause a subwoofer cabinet to resonate or even
dance, most subwoofer designers apply weight or mass to
the cabinet to minimize such disturbances. This leaves one
by product—"smeared bass". Vibrations translated from
the woofer to the cabinet actually dampen the bass signal
causing a loose and "fuzzy" sound.
The Depth integrates BalancedForce bass configuration to
nullify cabinet vibrations. Originally engineered for the
cost-no-object, state-of-the-art Statement™ E2 system,
BalancedForce uses two or more drivers mounted at oppos-
ing angles. The Depth's 3 drivers, spaced 120 degrees
apart, operate in exact opposition, resulting in maximum
cancellation. Therefore, the Depth delivers the ideal—
pure bass energy with a reduction in cabinet contributions
to the room as high as 25dB over traditional subwoofer
resonance solutions!
Servo-Controlled Dynamic Drivers
All dynamic drivers generate distortion caused by spider and
surround nonlinearities as well as voice coil inductive distur-
bances and variant motor strength during massive woofer
excursions. These challenges plague all subwoofer designers.
The result? Induced harmonic and intermodulated distortions
causing dramatic disturbances at high excursions. This occurs
significantly in almost all non-servo-controlled subwoofers.
To dramatically reduce these phenomena the Depth utilizes
servo monitoring and control via an advanced circuit that
corrects for any acoustic deviation from the pure audio sig-
nal, resulting in a 3 to 10-fold distortion reduction (depending
on SPL) over traditional dynamic driver technologies.
The Depth's low-pass filters achieve extremely precise
crossover points in both amplitude and time domain
resulting in seam-less blending with both MartinLogan and
non-MartinLogan products. By tailoring custom filters to
the main speaker roll-off characteristics, minimum group
delay results in cohesive integration and musical results.
25Hz Level Control
The Depth 25Hz level control allows custom sound tailor-
ing capabilities found in few subwoofers. A room, especially
when small, can greatly exaggerate bass in the 20–30Hz
range. The Depth’s 25Hz level control knob increases or
decreases lower bass to compensate for these room anom-
alies. The 25Hz level also allows increased deep bass if you
desire a subsonic sense of energy at the lowest frequencies.
TriLinear™Configuration
The use of three identical drivers maintains the low distor-
tion levels and optimal control of an efficient, small driver
while moving the same amount of air as a driver three
times larger. This allows powerful bass in a small package.
D
EPTH
A
DVANTAGES
Depth Advantages 17
BalancedForce™ For Cleaner Bass Low-Pass Filters Maximize Blending