Specifications

-
Appropriate Souad
level
For comfortable listening,
the
level
of
sound
froro
the
speaker
must
be
consider-
ably
louder
than
any
other
noises
whieh
may
be
heard
at
any
point
of
the room
(sor.rnd
frorn
the
projector,
people
walki-ng
in
pr""ngeway,
*i"ijl--rr."
amount
of
power
that
must
be fed
to
the
speaker
to
produce
an
adequate
sor:ad
output
de-
pends
on the
size-
of_the
projection
room
and
also
on
its
reverberation
charac-
teristlcs. With
the Bolex
BE-I4
loudspeaker,
the amount
of
audio_frequency
out_
put
required
from
the amplifier
in
a
room
with fittle
reverberation
is
about
I watt
per
100
mJ.
Notg: The
above
values
are
merely
approximationsl
they
should
be used
as
a
guide
and
the
operator
may
even
find
it
of advantage
lo
depart
from
them
in
particular
cases.
-
Sorne
Recom-rnen4ations
for
the
Operator
Do
not fcrget
that
the
avera€te
a.udience
is hlghly
critical
will
be
compared
to
that
s.11
:11-,,;.''1-,3eiona.l
onerators-
and
that
your
skill
Make
sure ihat
the
fuses
i-n
the
power
supply
circuiu
are
srrong
enough
to
pass
tiie
current
taken
by the
projector
and
auxiriary
room
lightingl
Before
the audience
is
seated,
run
a few feet
of film
on
the
projector
to
check
picture
and
sor-lrrd
quality
and
make
any adjustments
that
are
necessa"y.
S*onf cof*ir
uu4r
u DEUUTilE
ulr
your
equlpment
ear-Ly,
allowing yourself
plenty
of
bime
to
get
everything
ready
and
to
carry
out
the
necessary
tests
before
tLe
spectators
begin
to arrive.
ff you
have
to leave
yor.r
equipment
unattended
for
some
time
after
installing
itr
check
that
the
speakers
are
still
connected
and
"live"
for
sound
before
hosinnino fho chn
----
-.,-w.
Do
not leave
the
VOIUME
control
turned
up higher
than
position
"2"
or
,,l,,
when
gound
is
not being
usedr
as
otherwise
backgror-lnd
noise
from
the amplifier
wi-1l
be
heard
in
the speakers.
Turn
the volu-me
up only
at
the
start
of
itie fi1m,
when
the first
image
appears
on the
screen.
When
the
audience
is
largennthe
acoustic
properties
of
the
hall
are
altered,
making
it
necessary
to increase
the
souad volume
and
sometlmes
to
alter
the
tone, genenerally
by increasing
the
treble
control.
These
adiustmerrts
should
be
made
gradual-ly,
so that
bhe
audience
is not
aware
of it.
At
the
end of the
show,
switch
on
the room
lighting
and
svritch
off the
projec-
t"'"Llffin,I:';ffi,:I:"T:Id";:,I{"5'o'}
lfi"";ffiu'}I;"f;:,lt:"iiii:iI!f;J;"::::;"
35