Owner's Manual
Table Of Contents
ACCESS
SUBWOOFERS
User
Manual
D
Adjustment
of
low
cut
off
frequency
The cut
off
frequency
of
a
subwoofer
is
normally
in the region
of
60
to
100Hz.
This
is
always
dependent
on
the
particular
installation
and
listening position. A frequency
of
80Hz
is
a
good
compromise
for
effective bass
compared
to listening quality.
Enclosures
Access subwoofers were developed
for
vented
or
sealed box
according
to the reference
of
the
product.
Ij\
Warning
~
The
25
Aland
30
A1
must
only
be
used
in
a vented
box.
Please
refer to pages 6 and 7 for more information.
Ij\
Warning
~
The
30
A 1 DS must only be used in a sealed box. Please refer to
page
8
for
more
information.
Building
an
enclosure
The construction should always remain strong
and
rigid, to eliminate any unwanted resonances.
A
good
material such
as
MDF
(Medium
Density Fibreboard) will effectively ensure this
is
possible.
Choosing
the
correct
thickness
of
MDF
compared
to the surface area
decided,
is
also
critical to ensure the enclosure
does
not
vibrate. For this reason the general thickness
recommended
is
19mm
MDF. Any loose
components
such
as
the internal connections and cables should always be fixed securely inside.
Damping
material (foam
etc) covering all the internal walls
of
the enclosure, will further ensure it
is
free
from
unwanted resonances.
It
is
imperative
that
your
custom designed
subwoofer
enclosure remains securely
mounted
at
all times to the
vehicle.
Ij\
Warning!
~
The
improved
power
handling
has
allowed
Focal subwoofers to play
at
very
loud
sound volumes
For this reason,
we
recommend
caution be wisely
applied,
especially during long listening periods.
Excessive
volume
levels
of
more
than
11
OdS
can cause permanent hearing
damage.
Recommended
power
ratings
Access subwoofers
are
already highly efficient, with improved sensitivity. Therefore, their use with amplifiers will
produce
comfortable
listening pleasure.
However
used in a
more
high-end
system, with
more
powerful
amplification,
the
audio
quality will be greatly
improved.
It
is
very
important
to check
that
rated
power
of
the
amplifier
is
suitable to the subwoofers.
Otherwise
they
may
distort,
or
possible
damage
could
occur.
Always consult the owners
manual
of
the principal source (head
unit/amplifier),
to ensure the
power
rating
is
compatible.
A safe
guide
is
to ensure the
maximum
power
of
the
amplifier
is
not greater than the
nominal
power
of
the speakers.