JBL 6290 - Remember the Dividing Network (Crossover); Speaker Cables; Type of Wire; Damping Factor

2.7.4
REMEMBER
THE
DIVIDING
NETWORK
(CROSSOVER)
If
the
amplifier
Is
connected
to a
multi-way
loudspeaker
system
that
Includes
a
passive,
high-level
dividing
network
(crossover),
be
sure
the
network
Is
rated
to
handle
the
amplifier's
power.
Pre-
packaged
speaker
system
power
ratings
already
take
the
crossover
Into
account.
If
you
obtain
separate
components
and
assemble
a
system,
the
chances
are
that
the
higher
frequency
drivers
will
be
rated
at
less
power
than
the
woofer(s).
This
works
out
overall
because
the
higher
frequency
drivers
tend
to
be
more
efficient
(more
sound
per
watt).
In
fact,
higher
sensitivity
In
the
high
frequency
components
usually
requires
some
attenuation
to
be
applied
In
the
dividing
network.
A
3
dB
more
sensitive
driver
must
be
driven
with
half
the
power
to
generate
the
same
sound
level.
For
example,
consider
a
typical
two-way
system
with
a
200
watt
woofer
and
50
watt
high
frequency
compression
driver.
The
woofer,
1
meter
from
Its
enclosure,
generates
100
dB
SPL
with
1
watt
at
Its
Input,
and
the
compression
driver,
1
meter
from
Its
horn,
generates
106
dB
SPL
at 1
watt
input.
If
both
components
are
driven
by a
200
watt
program
signal,
the
compression
driver
will
be
6
dB
too
loud
(four
times
the
level
of
the
woofer).
Therefore,
the
crossover
network
must
provide
6
dB
of
attenuation
for
the
compression
driver,
lowering
Its
Input
power
to 50
watts.
The
200
watt
amplifier
turns
out
to be
perfectly
suited
to
driving
this
system,
even
though
one
driver
Is
rated
at
just
50
watts.
2.8
SPEAKER
CABLES
2.8.1
TYPE
OF
WIRE
A
number
of
companies
offer
various
special
’’speaker
cables”
which
are
claimed
to
vastly
Improve
the
signal
delivered
from
amplifier
to
loudspeaker
system.
Some
special
cables
have
merit,
others
may
actually
be
detrimental,
and
the
value
will
have
to
be
determined
by
the
user.
For
most
applications
two
factors
need
to
be
considered;
DC
resistance
and
durability.
Generally,
the
larger
the
wire
gauge,
the
better.
DC
resis-
tance
is
lower
with
larger
wire,
more
of
the
amplifier
power
gets
to
the
loudspeaker,
and
damping
factor
Is
not
degraded.
More
strands
of
wire
In a
given
wire
gauge
are
beneficial
because
they
let
the
cable
handle
more
flexing
without
fatigue.
2.8.2
DAMPING
FACTOR
The
higher
the
damping
factor
of
an
amplifier,
the
greater
Its
ability
to
control
unwanted
speaker
cone
movements
--
especially
at
low
frequencies.
To
understand
how
a
high
damping
factor
Improves
sound
quality,
you
must
first
understand
some
basic
principles.
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