PSB Powered Subwoofers - B. Subwoofer Placement

you
want.
In
smaller
rooms,
sound
attenuation
tends
to
be
offset
by
reinforcement
from
wall
reflections.
In
larger
spaces,
sound
has
to
travel
to
reach
the
reflecting
sur-
faces
and
then
to
your
ears,
which
means
it
has
to
be
louder
to
begin
with.
With
tra-
ditional
full-range
speakers,
that
involves
properly
matching
amplifier
power,
speaker
sensitivity,
impedance
and
power
handling.
Most
of
the
power
goes
to
reproducing
bass,
so
using
powered
subwoofers
and
separate
midrange/treble
satellites
allows
for
a
conservative
draw
on
power
from
your
main
amplifier,
while
ensuring
a
good
match
between
the
low-frequency
amplifier
and
the
woofer.
After
size,
the
most
important
aspect
of
a
listening
room
is
its
shape.
In
any
room,
sound
reflects
off
the
walls,
ceiling,
and
floor.
If
the
distance
between
two
opposite
parallel
surfaces
is
a
simple
fraction
of
the
wavelength
of
a
particular
frequency,
notes
of
that
frequency
will
bounce
back
and
forth
in
perfect
phase-an
effect
called
a
standing
wave
or
room
mode.
At
some
point
in
the
room,
this
note
will
be
reinforced
substantially;
at
others
it
will
cancel
out
almost
entirely.
If
the
prime
listening
seat
is
placed
at
either
of
these
locations,
the
note
will
be
a
horrible
boom
or
virtually
non-
existent.
Almost
all
rooms
are
susceptible
to
some
standing
waves
at
low
frequen-
cies,
but
careful
positioning
of
the
speakers
and
the
listening
seat
can
minimize
the
effects.
The
only
way
to
find
out
what
works
best
is
by
experimentation.
Speaker
positioning
may
be
fairly
limited
in
your
room
to
still
get
proper
imaging,
and
some
of
these
positions
may
still
result
in
standing
waves.
Use
of
a
subwoofer
or
two
makes
this
more
controllable.
Positioning
of
the
bass
speakers
has
almost
no
impact
on
imaging,
so
a
subwoofer
can
be
positioned
with
only
standing
waves
in
mind.
B.
Subwoofer
Placement
The
loudest
bass
output
from
a
subwoofer
comes
from
corner
placement.
The
outward
flaring
of
walls
from
a
corner
focuses
low
frequencies,
giving
them
no
place
to
go
but
toward
the
listener.
In
the
case
of
subwooofers,
there
is
no
penalty
in
overall
balance
for
this
maximal
bass,
since
your
main
speakers
can
be
located
elsewhere.
In
most
cases,
there
should
be
plenty
of
bass
from
corner
placement.
If
you
are
seated
in
a
null
spot
where
sound
from
the
subwoofer
is
cancelled
or
diminished
by
out-of-phase
reflections,
you
will
have
to
move
either
the
subwoofer
or
your
listening
position
until
you
get
the
desired
bass.
Flipping
the
phase
control
180
degrees
sometimes
may
make
a
difference,
especially
if
the
null
is
a
product
of
cancellations
caused
by
interaction
with
low
frequencies
from
your
main
speakers.
If
the
opposite
is
happening,
where
direct
and
reflected
bass
waves
converge
in
phase
and
produce
too
strong
a
peak
at
your
listening
position,
you
can
change
position
or
change
your
sub's
level
control
(or
possibly
the
crossover
frequency
chosen).
The
best
method
for
positioning
a
subwoofer
is
to
put
the
subwoofer
in
your
listening
chair,
then
play
music
with
lots
of
bass
through
the
system
(something
with
steady
low
frequencies
or
continuous
test
tones).
Move
around
the
room
and
note
where
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