Owner's Manual

IMPORTANCE
OF
A DEEP SEAL
Note: Hearing amplifier devices
come
with
a large
selection
of
eartips, including
two
sizes
of
3-flange
eartips
with
long
stems. Depending on
your
ear
geometry,
the
longer
stems may
allow
the
deepest
seal.
A
deep
eartip
seal ensures
the
best
performance
and
prevents
the
"hollow
voice"
sound, called
the
occlusion effect.
The occlusion
effect
is
caused
by
sound
transmission
into
the
ear
from
vibration
of
the
ear canal
wall
when
the
ear
is
occluded
by
an
eartip.
The
vibration
comes
from
sound pressure
developed
in
the
back
of
the
mouth.
The occlusion
effect
is
most
commonly
caused
by
vibration
from
a person's
own
voice,
especially
from
speaking
the
sounds
"ee"
and
"uu,"
or
from
playing a brass
or
woodwind
musical instrument.
The occlusion
effect
is
worse
when
there
is
a
shallow insertion
of
the
eartip.
Deeply-sealed eartips reduce
the
occlusion effect.
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