Specifications
so}p
HINTS FROM
A
SOU-Np
ENGINEER
I. SOUIVD
PROJECTION
Acoustics
oI
the
Proiection
Room
Curtains
of
heavy
materiaf
will
do
much
to
alter the
acoustic
characteristics
of
a roomr
to
make
thera
suitable
and
to
prevent
the
occurence
of
echoes
that
inter-
fere
with
good
reproductlon.
Panels
of
sound absorbent
material
can
also
be
used
with
good
results.
Do
not
forget
that
an
empty room
has
more
pronor.mced
reverbe-
ration
than
one
that
is
fitled
to
capacity.
Besides
the
suitability
for
motion picture
screenj-ngs
and
the
comfort
i-t
offers
to
the
audience,
the
projecti-on
room
must
afso
have good
acoustics.
The
best
results
will
be obtained
in
a room
in
which
reverberation
has
been
sui-tably
re-
duced.
A
certain
degree
of reverberation
is
nevertheless
useful,
since
j-t
tends
to
rrliven
uptr
the
reproductlon
of the
sould,
especially
of music.
Reverberation
i-s
produced
by
the
mixlng
of
the
soimd
waves
coming
4irectly
from
the
speaker
and
of
those
that
have
been
reflected
by ffoors,
l+alis,
ceir1ng
etc.
and
which
are
heard
as
a
nild
echo.
-
Arranqement
of Projector
and
Spe.akers
The
ideaf
solution
is
to
install
the
projector
in
its
own
separate
booth, rn
this
case,
the
auxiliary
speaker
BE-14
(rf
r.)
is
used"
in
the
auditorium,
while
the
speaker
placed-
in
the
projector
1id
is
used
by
the
operator
for
nonitoring
purposes'
the
speakers
being
regulated
with
the
special
speaker
distributor
box
control.
If
this
arrangenent
proves
to
be impractical,
th;
projector
may
be
set
up in
the auditoriumr
preferably
behind
the audience
rather
than
in
the
nlddle
of
it'
to
avoid
distraction
of
attention
by
the noise
of
the
projector.
The
pro-
jector
can
a.l-so
be
set
up in
an adjoining
room,
provided
therl
j-i
a door
or
other
opening
conveniently
located
to
permit
projeetion
from
one
room
to
the
o
ther,
when
the
projector
is
set
up
in
the
auditorium,
ei-tirer
one
or
be
used. the
main
speaker
i-s
best
placed
as
near
as
possible
si-de
or beneath
it,
but
not
too
low.
The
speaker
BE-14
suits
this
purpose
very
we1l,
since
it is
mounted
on
a stand.
If
a
special
perforated
screen
for
sor:nd nrn-ioo-|-inn
ker
nav
be
pllced
directly
behind
#Tl
i;:':::i:l
:;
il:t:3tiilr*f;"t::ff5""-
wilJ-
appear
to
come
fron
the
picture.
hnih
cnoollorc
^D)
-*,.
- -*;1
i.n tlro
q^roar
ho-
i
6
7A
tu