App. 1.5 Susceptance And Conductance, B/G; App. 1.5.1 Susceptance, B - Madsen zodiac Reference Manual

App. 1 MADSEN Zodiac immittance methodology and features
as a sudden pressure drop toward, but not necessarily reaching, atmospheric pressure (0 daPa). This is repeated until the
pressure is equalized or until the test time has elapsed. The pressures at which the tube opens and closes are reported as
test results.
Typically, an initial build-up of positive pressure will cause the Eustachian tube to open spontaneously. In order to avoid
premature spontaneous pressure equalization related to positive pressure build-up, the pump speed should be kept at a
maximum of 50 daPa/s.
The pressure range available for positive and negative pressures (including 400 daPa and -600 daPa) is commonly used in
ETF-P testing.
App. 1.5 Susceptance and Conductance, B/G
admittance (Y)
The
the two components
The admittance magnitude is the vector length derived from
the Cartesian graph as shown.
App. 1.5.1 Susceptance, B
Susceptance
of energy flow through the
Compliant elements
•
muscles, and the air in the ear canal and middle ear.
Mass elements
•
pression or expansion).
The compliance
Compliant Susceptance
•
• Mass Susceptance
Susceptance
The total
146
of the ear consists of the contribution of
Susceptance (B)
and
is determined by the ease with which energy flows through the
Mass elements
are the tympanic and round window membranes, the ossicular ligaments, the middle ear
are the ossicles and the slugs of air in the middle ear mastoid air cells (moving as units without com-
and mass contribution to the total
is greater with low frequencies and gradually decreases with higher frequencies.
is greater with high frequencies and gradually decreases with lower frequencies.
is the algebraic sum of the positive
Conductance (G)
.
of the ear.
Susceptance is frequency dependent.
Compliance
Compliant elements
Mass
and the negative contributions, jB + (-jB).
Otometrics - MADSEN Zodiac
of the ear and the ease