Hybrid Audio Technologies Legatia SE - Manual (Page 8)

Legatia SE User’s Manual ©Hybrid Audio Technologies Page 8 of 73
associated with most composite cones, but still be rigid enough for upper midbass response. All
cones have been treated with a water resistant element at the rear to accommodate door mounting,
or other areas prone to occasional contact with liquid.
All Legatia SE designs offer an outstanding extended frequency response; the usable frequency
range of the Legatia SE midrange and midbass drivers is at least six full octaves, and in many cases,
seven or more octaves of usable bandwidth with proper installation, aiming, set-up, and tuning. And
because of the employed cone technology which boasts exceptional off-axis response, described
above, all Legatia SE drivers offer exceptional off-axis bandwidth as well, exceeding five octaves for
all designs.
Suspension
All Legatia SE midrange and midbass drivers include an inverted surround made of 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
surround, which acts as an air seal between the cone and the basket, adds to the restoring force of
the spider. Another function of the surround is to absorb cone flexure waves as they are transferred
up the cone. You'll also know a Legatia SE midrange and midbass design by its inverted surround;
this design feature allows for the use of a smaller height grille, and more flexibility in mounting
options. The inverted surround is also instrumental for taming edge mode distortion.
The spider material was chosen for optimal performance in all models; 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.
Basket
The basket of the Stage VI Legatia SE series drivers are a shared design with the same
size/diameter drivers in the Stage V Legatia series, for easy upgrade potential; the frames of
similarly-sized drivers are interchangeable in mounting topology. The basket is a high-quality cast
aluminum design, and contains a large flange providing for the mounting of the driver via four screw
holes. The Legatia SE frame features large openings behind the cone to eliminate chuffing and other
aerodynamic-based noises, as well as provides adequate communication to the back of the cone for
acoustic suspension and proper operation.
Thiele/Small Parameters Introduction
Acoustics pioneers Neville Thiele and Richard Small developed a way to predict speaker
performance and frequency response. These parameters are known collectively as “Thiele/Small
Parameters”, and are divided into physical characteristics and response parameters:
The Physical Characteristics of a speaker are:
Re:
The D.C. resistance of the voice coil measured in Ohms.
Sd: The surface area of the speaker’s cone.
BL: The magnetic strength of the motor structure.