Hybrid Audio Technologies Legatia - Manual (Page 8)

Legatia User’s Manual ©Hybrid Audio Technologies Page 8 of 65
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 V Legatia series drivers are a shared design with the same size/diameter
drivers in the Stage VI Legatia Special Edition 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 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.
Mms: The total moving mass of the speaker including the small amount of air in front of and behind
the cone.
Cms: The stiffness of the driver’s suspension.
Rms: The losses due to the suspension.
The Thiele/Small Response parameters are:
Re:
The D.C. resistance of the voice coil measured in Ohms.
Sd: The surface area of the speaker.
Fs: The resonant frequency of the speaker.
Qes: The electrical “Q” of the speaker.
Qms: The mechanical “Q” of the speaker.
Qts: The total "Q" of the speaker.
Vas: The volume of air having the same acoustic compliance as the speaker’s suspension.
Application to Thiele/Small Parameters to Legatia Designs
Enclosure Recommendations
The mechanical and electrical parameters of the Legatia midrange and midbass drivers are amenable
to a variety of different installations and speaker locations. In a typical vehicular installation, Hybrid
Audio Technologies recommends that the Legatia drivers be placed in an “infinitely large” enclosure,
which is more notably known as “infinite baffle.” Small sealed enclosures are not needed to be
constructed, nor are typically recommended in most circumstances for any of the Legatia range of