Hybrid Audio Technologies Legatia SE Carbon - Manual (Page 11)

Legatia SE Carbon User’s Manual ©Hybrid Audio Technologies Page 11 of 30
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 L4SE is a large 25.5mm (1-inch), which is the proper balance between
size and moving mass in super high-end mobile audio midranges/full-range drivers. 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 unique double-S shaped surround is treated fine cloth which is highly consistent, and does not
suffer the variance one might find in natural rubbers, foam, or untreated cloth. The 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
As noted in the introduction, the SE Carbon is a complete departure from the typical Hybrid Audio
Technologies philosophy of point-source midbass and midrange (full-range) drivers. The composite
cone, although not ideal for wide-bandwidth operation, does an aplomb job of effectively recreating
midbass and lower to middle midrange tones effectively. The Legatia SE Carbon midbass drivers
include a carbon fiber diaphragm with low moving mass. Carbon fiber is acknowledged as being an
exceptionally strong material, but exhibits edge-mode distortion at high frequency, and therefore
should be appropriately filtered using active crossovers, or custom passive crossovers. By nature,
the carbon fiber cone and dustcap are water resistant.
Hybrid Audio Technologies recommends the use of a low-resonance tweeter to be used in concert
with the Legatia L4SE Carbon, such as the Legatia L1 Pro or Legatia L1 Pro R2. When placing the
midbass and tweeter in close proximity to each other, one can achieve having all imaging cues
emanating from the pair of drivers in an installation, ensuring stable stereo imaging across the
fundamental frequencies which define image placement and definition. Naturally, crossover filter
selection is paramount.
Shorting Cup
The L4SE Carbon uses a copper shorting cup. The shorting cup consist of an optimally sized and
placed copper (Cu) cup to create a total inductance profile that is not just low, but flat over stroke,
frequency, and power. Inductance is the number one limiter of high frequency extension and
modulation of inductance with stroke, frequency and power, and is the primary source of
intermodulation distortion (IMD).