Hybrid Audio Technologies Legatia SE - Manual (Page 36)

Legatia SE User’s Manual ©Hybrid Audio Technologies Page 36 of 73
Motor
The motor of the L8SE is paramount to the performance of the driver, providing for a flat and wide BL
curve (as a learning note, BL is the equivalent of torque in a car; a car with a flat and constant torque
curve provides much better acceleration and performance than a car with a peaky, non-constant
torque curve). The BL curve is flat and extended, yielding 19mm of two-way linear excursion,
resulting in the L8SE being able to accurately track the input signal. Reduced distortion and greater
dynamics are the immediate sonic benefits. The motor of the L8SE includes an opposing double-
stacked NdFeB magnet to improve restorative force, compliance, motor strength, displacement, and
power handling. The magnet assemblies are fully surrounded by the voice coil.
Voice Coil
The voice coil diameter of the L8SE is a large 35.55mm (1.4-inch), which is the proper balance
between size and moving mass in super high-end mobile audio midranges/midbass. The voice coil
diameter serves several key functions: elevated power handling, dissipation of heat (thereby lowering
power compression), and maximizing the size of the magnet assembly for enhanced motor
compliance. The voice coil is high-purity aluminum, which is superior to copper for heat dissipation,
as well as significantly reduced moving mass. The result is an extremely light weight winding with
good power handling and low inductance.
Suspension
The inverted surround is butyl rubber which is highly consistent, and does not suffer the variance of
natural rubbers. This rubber surround terminates mechanical vibrations well, having a low stiffness
for positive damping of resonances. The spider material was chosen for optimal performance; the
spider is a 90/10 cotton/Nomex blend with single-dip low viscosity phenolic. This material provides
the stiffness desired without being overly brittle or stiff, where vibrations in the spider are well damped
and do not translate into the former or the cone.
Cone
Like other Legatia SE midrange designs, you will find no composite or metal cone materials used on
the L8SE, as our approach to point-sourcing is to allow the Legatia SE midbass/midrange driver to
effectively play into middle and upper midrange frequencies. The Legatia L8SE is a cone-type driver
consisting of a proprietary hybrid paper diaphragm with extremely low moving mass. Paper is widely
acknowledged as the best-damping material, as it provides the near optimum balance of strength and
weight. The cone has been treated with a water resistant element at the rear to accommodate door
mounting, or other areas prone to occasional contact with liquid. The cone design offers a wide
dispersion pattern to make for flexible installation and speaker location. The Legatia L8SE has an
outstanding extended frequency response; the usable frequency range of this driver exceeds seven
complete octaves of usable bandwidth on-axis (40 Hz – 5,000+ Hz). Even off-axis, the L8SE faithfully
recreates more than five full octaves of information, for the ultimate midrange/full-range driver.
Phase Plug and Shorting Cup
The L8SE comes equipped with a phase plug pole piece extension at the center of the cone. The
phase plug is aluminum and, by design, ensures enhancement of the total inductance profile,
providing much of the inductance reduction benefits noted. The phase plug is plated with rose-tinted