JBL K2S4800 (serv.man2) User Manual / Operation Manual ▷ View online
CHAPTER 4 – AMPLIFIER RECOMMENDATIONS
No single type of amplifier is
specified for use with the S4800
system. The speakers are highly
efficient and will operate
adequately with an amplifier or
receiver of 70-100 watts.
specified for use with the S4800
system. The speakers are highly
efficient and will operate
adequately with an amplifier or
receiver of 70-100 watts.
However, the transient response
and audio definition of a high-end
system such as the S4800 will pick
up all inefficiencies and distortion
in an amplifier system. For full-
range operation, the S4800 system
can be used with an amplifier/
receiver of as little as 30 watts.
Amplifiers/receivers of
100-300 watts will ensure optimum
system performance.
and audio definition of a high-end
system such as the S4800 will pick
up all inefficiencies and distortion
in an amplifier system. For full-
range operation, the S4800 system
can be used with an amplifier/
receiver of as little as 30 watts.
Amplifiers/receivers of
100-300 watts will ensure optimum
system performance.
There is no effective limit to the
power handling capabilities of the
S4800 loudspeakers when driven
by consumer audio amplifiers. No
damage will occur when used with
high-powered components. Source
impedance is an important criterion
in selecting an appropriate unit; the
selected amplifier(s) should have a
very high current capacity and
must be capable of driving a low
impedance load.
power handling capabilities of the
S4800 loudspeakers when driven
by consumer audio amplifiers. No
damage will occur when used with
high-powered components. Source
impedance is an important criterion
in selecting an appropriate unit; the
selected amplifier(s) should have a
very high current capacity and
must be capable of driving a low
impedance load.
For bi-wiring applications, four
identical amplifiers or two dual-
channel units may be used,
although specialized low-frequency
and high-frequency amplifiers offer
clear advantages.
identical amplifiers or two dual-
channel units may be used,
although specialized low-frequency
and high-frequency amplifiers offer
clear advantages.
NOTE: When using separate high-
and low-frequency amplifiers with
dual wires to each speaker, the
amplifiers must have exactly the
same gain structure, or one of them
must have a level control to adjust
the gain between the two
amplifiers. If four amplifier
channels are used, the high-
frequency amplifier may be up to
6dB less powerful than the low-
frequency amplifier. Due to the
power versus frequency
distribution of the music, the low-
frequency section requires
approximately four times the power
of the high-frequency section.
and low-frequency amplifiers with
dual wires to each speaker, the
amplifiers must have exactly the
same gain structure, or one of them
must have a level control to adjust
the gain between the two
amplifiers. If four amplifier
channels are used, the high-
frequency amplifier may be up to
6dB less powerful than the low-
frequency amplifier. Due to the
power versus frequency
distribution of the music, the low-
frequency section requires
approximately four times the power
of the high-frequency section.
JBL specialist dealers can
recommend amplification to best
suit individual needs. In all cases,
the left and right amplifiers for each
section must be identical. Make
sure that the input sensitivity of the
two amplifiers is equal or that input
level controls are provided to
maintain the proper low to mid/high
balance. If two identical stereo
amplifiers are chosen, each
amplifier may be located near a
loudspeaker and drive low-
frequency and high-frequency
sections through short wire runs.
recommend amplification to best
suit individual needs. In all cases,
the left and right amplifiers for each
section must be identical. Make
sure that the input sensitivity of the
two amplifiers is equal or that input
level controls are provided to
maintain the proper low to mid/high
balance. If two identical stereo
amplifiers are chosen, each
amplifier may be located near a
loudspeaker and drive low-
frequency and high-frequency
sections through short wire runs.
9
CHAPTER 5 – PLACEMENT AND SETUP CONSIDERATIONS
The S4800 loudspeaker system is
designed to be less affected by
room acoustics than conventional
imaging systems. However, it is
very sensitive to overall symmetry,
and proximity to walls, ceilings and
corners.
designed to be less affected by
room acoustics than conventional
imaging systems. However, it is
very sensitive to overall symmetry,
and proximity to walls, ceilings and
corners.
Ideally, any listening room should
contain a combination of live
surfaces (e.g., walls and windows)
and absorbent surfaces (e.g.,
drapes, carpets, upholstery). If the
distance from floor to ceiling is
short, it is preferable that one
surface has an absorbent covering.
With the S4800, it is most important
to be able to accommodate the
optimum listening area that is
defined by the 100° horizontal/60°
vertical coverage pattern of the
horn.
contain a combination of live
surfaces (e.g., walls and windows)
and absorbent surfaces (e.g.,
drapes, carpets, upholstery). If the
distance from floor to ceiling is
short, it is preferable that one
surface has an absorbent covering.
With the S4800, it is most important
to be able to accommodate the
optimum listening area that is
defined by the 100° horizontal/60°
vertical coverage pattern of the
horn.
The listener should be centered in
front of the speakers, and furniture
should be of an appropriate height
so that when the listener is sitting,
his or her ears are level with the
horn (approximately 32 inches/
80cm), as illustrated in Figure 2.
front of the speakers, and furniture
should be of an appropriate height
so that when the listener is sitting,
his or her ears are level with the
horn (approximately 32 inches/
80cm), as illustrated in Figure 2.
CAUTION: The S4800 is a massive
system comprising materials
chosen for their density, with its
system comprising materials
chosen for their density, with its
weight concentrated in a relatively
narrow area. Verify the integrity of
the floor surface before placing
and setting up the speakers. See
Floor Requirements.
narrow area. Verify the integrity of
the floor surface before placing
and setting up the speakers. See
Floor Requirements.
If possible, the distance between
the speakers should be the same
as the distance between each
speaker and the listening area.
Angle the speaker in toward the
listener so that when seated, the
listener can look straight into the
center of the speaker (Figure 7). As
the distance increases between
the speakers, increase the inward
angle of the speaker.
the speakers should be the same
as the distance between each
speaker and the listening area.
Angle the speaker in toward the
listener so that when seated, the
listener can look straight into the
center of the speaker (Figure 7). As
the distance increases between
the speakers, increase the inward
angle of the speaker.
The imaging qualities enable the
speakers to be placed relatively far
apart from each other. In addition,
the low-frequency alignment fea-
ture enables placing the speakers
near, or even in, a corner without
producing an overabundance of
bass. This corner placement ability
allows optimum performance even
in small rooms.
speakers to be placed relatively far
apart from each other. In addition,
the low-frequency alignment fea-
ture enables placing the speakers
near, or even in, a corner without
producing an overabundance of
bass. This corner placement ability
allows optimum performance even
in small rooms.
The S4800 system can operate
fairly close to the wall. Leave
enough clearance between the
back of each speaker and the wall
to allow for making the connections
fairly close to the wall. Leave
enough clearance between the
back of each speaker and the wall
to allow for making the connections
on the back of the speaker
(approximately 2 inches – 3 inches
is sufficient), and to avoid
interference with the performance
of the tuned port. Remember that
these speakers weigh close to 143
lb (65kg) each and cannot be easily
moved.
(approximately 2 inches – 3 inches
is sufficient), and to avoid
interference with the performance
of the tuned port. Remember that
these speakers weigh close to 143
lb (65kg) each and cannot be easily
moved.
FLOOR REQUIREMENTS
The floor in the location selected
for setting up the S4800 speakers
must be capable of supporting a
load of 143 lb (65kg) per speaker.
Because of the coupling effect of
the stainless-steel feet, a flat, hard
surface such as wood or linoleum
is preferable. However, the design
of the loudspeaker’s coupling
system, along with the speaker’s
extreme weight, should result in
excellent performance on any
surface, even on carpets.
for setting up the S4800 speakers
must be capable of supporting a
load of 143 lb (65kg) per speaker.
Because of the coupling effect of
the stainless-steel feet, a flat, hard
surface such as wood or linoleum
is preferable. However, the design
of the loudspeaker’s coupling
system, along with the speaker’s
extreme weight, should result in
excellent performance on any
surface, even on carpets.
To prevent indentations on wood or
linoleum floors caused by the
weight of the loudspeaker, always
utilize the enclosed coasters. Do
not set up the S4800 system directly
on a ceramic tile floor; the
concentrated weight might cause
the tiles to crack.
linoleum floors caused by the
weight of the loudspeaker, always
utilize the enclosed coasters. Do
not set up the S4800 system directly
on a ceramic tile floor; the
concentrated weight might cause
the tiles to crack.
Figure 7.
Room placement of S4800 speaker system.
10
The S4800 has an HF trim switch
mounted on the network panel on
the rear of the enclosure. The
HF Trim Switch
mounted on the network panel on
the rear of the enclosure. The
HF Trim Switch
2 adjusts the high-
frequency level over the range of
approximately 1000Hz to 10kHz. The
+1dB position gives the highest HF
output and measures the most
level. 0dB reduces the HF level by
1dB, and the – 1dB position
reduces the HF level by an
additional 1dB.
approximately 1000Hz to 10kHz. The
+1dB position gives the highest HF
output and measures the most
level. 0dB reduces the HF level by
1dB, and the – 1dB position
reduces the HF level by an
additional 1dB.
Although the range of these control
settings is rather small, each of
them operate over a reasonably
wide frequency range and thus
have a noticeable effect on the
overall tonal balance of the system.
It is recommended that the system
first be played with the switch in
the middle position. This setting
gives the most uniform
measurements in a controlled
environment. Of course, we are
interested in producing the most
pleasing sound in your environment
with your choice of program
material. It is, therefore,
recommended that the HF Trim
Switch
settings is rather small, each of
them operate over a reasonably
wide frequency range and thus
have a noticeable effect on the
overall tonal balance of the system.
It is recommended that the system
first be played with the switch in
the middle position. This setting
gives the most uniform
measurements in a controlled
environment. Of course, we are
interested in producing the most
pleasing sound in your environment
with your choice of program
material. It is, therefore,
recommended that the HF Trim
Switch
2 be tested in its various
settings on a variety of program
material. Once you become familiar
with their individual character, you
should have no difficulty
determining the setting that
produces the most pleasing,
natural sound in your room with
your equipment.
material. Once you become familiar
with their individual character, you
should have no difficulty
determining the setting that
produces the most pleasing,
natural sound in your room with
your equipment.
0 Mid-/High-Frequency Input
Terminals: For bi-wire configura-
tions, connect the speaker wires
for the mid- and high-frequency
ranges to these terminals.
1 Shorting Straps: Leave the
shorting straps in place only if you
are using the passive single-wire
connection option described on
page 13. Otherwise, remove the
straps to prevent possible damage
to the speakers or your electronics.
2 HF Trim Switch: This switch
allows you to adjust the output of
the high-frequency transducers to
compensate for the acoustics of
your room. The +1dB position
increases the output, the 0dB
position is a flat-level position, and
Terminals: For bi-wire configura-
tions, connect the speaker wires
for the mid- and high-frequency
ranges to these terminals.
1 Shorting Straps: Leave the
shorting straps in place only if you
are using the passive single-wire
connection option described on
page 13. Otherwise, remove the
straps to prevent possible damage
to the speakers or your electronics.
2 HF Trim Switch: This switch
allows you to adjust the output of
the high-frequency transducers to
compensate for the acoustics of
your room. The +1dB position
increases the output, the 0dB
position is a flat-level position, and
the –1dB position decreases the
output. Each position will affect the
tonal balance over a wide
frequency spectrum. Experiment by
placing the switch in each position
while listening to familiar program
material and choose the position
that suits your room acoustics and
listening preferences. You may find
after a few months, once the
transducers have settled in, that
another adjustment is necessary.
This is normal. The switch may be
adjusted using a flat-head
screwdriver.
output. Each position will affect the
tonal balance over a wide
frequency spectrum. Experiment by
placing the switch in each position
while listening to familiar program
material and choose the position
that suits your room acoustics and
listening preferences. You may find
after a few months, once the
transducers have settled in, that
another adjustment is necessary.
This is normal. The switch may be
adjusted using a flat-head
screwdriver.
3 Low-Frequency Input Terminals:
For bi-wire configurations, connect
the speaker wires for the low-
frequency range to these terminals.
For bi-wire configurations, connect
the speaker wires for the low-
frequency range to these terminals.
CHAPTER 6 – S4800 SWITCH OPERATIONS
11
Figure 8. S4800 controls and connections.
SHORTING STRAPS
The S4800 is shipped with shorting
straps installed between its low-
frequency and high-frequency
terminals. Please see Figure 8.
straps installed between its low-
frequency and high-frequency
terminals. Please see Figure 8.
To prepare the S4800 for bi-wire
operation, these straps must be
removed by completely unscrewing
each binding-post knob, removing
the straps, and replacing the knob.
Speaker wires can then be
connected to each set of terminals
(see Figure 9).
operation, these straps must be
removed by completely unscrewing
each binding-post knob, removing
the straps, and replacing the knob.
Speaker wires can then be
connected to each set of terminals
(see Figure 9).
AMPLIFIER
CONNECTIONS
CONNECTIONS
IMPORTANT: Turn all amplifiers off
before connecting or disconnecting
S4800 loudspeakers. Making
connections while an amplifier is
operating could seriously damage
the loudspeaker system and void
the warranty. All amplifiers must
also be turned off before
connecting or disconnecting
cables at the amplifier or
preamplifier inputs.
before connecting or disconnecting
S4800 loudspeakers. Making
connections while an amplifier is
operating could seriously damage
the loudspeaker system and void
the warranty. All amplifiers must
also be turned off before
connecting or disconnecting
cables at the amplifier or
preamplifier inputs.
All connections between the amp-
lifier(s) and the S4800 loudspeaker
system are made at the terminals
located on the back of the
enclosure (see Figures 9 through
12).
lifier(s) and the S4800 loudspeaker
system are made at the terminals
located on the back of the
enclosure (see Figures 9 through
12).
The left-hand terminals (black
stripe) are negative, and the right-
hand terminals (red stripe) are
positive. These correspond to the
negative and positive conductors in
the speaker wire. Each speaker
wire contains two conductors, one
of which will have a stripe, color
markings or a ridge. Assign one of
the two conductors as the negative
conductor and the other as the
positive conductor. Use these same
designations for all system wiring.
Always connect the conductors of
the speaker wire appropriately to
the corresponding negative and
positive terminals on all system
components. This will ensure that
all components will work together
(“in phase”). Con-necting the
speakers out of phase will not
damage them but will result in
reduced low-frequency output and
impaired stereo effect.
stripe) are negative, and the right-
hand terminals (red stripe) are
positive. These correspond to the
negative and positive conductors in
the speaker wire. Each speaker
wire contains two conductors, one
of which will have a stripe, color
markings or a ridge. Assign one of
the two conductors as the negative
conductor and the other as the
positive conductor. Use these same
designations for all system wiring.
Always connect the conductors of
the speaker wire appropriately to
the corresponding negative and
positive terminals on all system
components. This will ensure that
all components will work together
(“in phase”). Con-necting the
speakers out of phase will not
damage them but will result in
reduced low-frequency output and
impaired stereo effect.
Speaker wires may be fastened to
the terminals by several methods.
The most positive connection is
made by directly connecting clean,
bare connectors (exposed by
stripping the ends of the wire) to
the terminal posts.
the terminals by several methods.
The most positive connection is
made by directly connecting clean,
bare connectors (exposed by
stripping the ends of the wire) to
the terminal posts.
For this type of connection, loosen
the knobs on the terminals and
insert the exposed (bare) ends of
each speaker wire into the hole
exposed on the terminal shaft
( + to +, – to – ) (see Figure 12).
Refasten the knob on each terminal
so that a snug connection is
achieved. Do not apply excessive
force and do not overtighten. To
avoid a short circuit, trim off any
excess wire that is not in contact
with the binding post contact
surfaces.
the knobs on the terminals and
insert the exposed (bare) ends of
each speaker wire into the hole
exposed on the terminal shaft
( + to +, – to – ) (see Figure 12).
Refasten the knob on each terminal
so that a snug connection is
achieved. Do not apply excessive
force and do not overtighten. To
avoid a short circuit, trim off any
excess wire that is not in contact
with the binding post contact
surfaces.
S4800 terminals are also designed
to accept spade or banana-type
connectors, which are fastened to
the ends of the wires and, in turn,
are attached to the terminal posts.
to accept spade or banana-type
connectors, which are fastened to
the ends of the wires and, in turn,
are attached to the terminal posts.
WIRING
CONFIGURATIONS
CONFIGURATIONS
As mentioned earlier, the S4800
speakers may be connected to the
amplifier(s) by one of these
methods: passive or bi-wire. Each
method (described on page 13) has
its own advantages, and the
loudspeaker system will deliver
superb performance with both
methods.
speakers may be connected to the
amplifier(s) by one of these
methods: passive or bi-wire. Each
method (described on page 13) has
its own advantages, and the
loudspeaker system will deliver
superb performance with both
methods.
Each speaker is shipped with
external shorting straps in place
(see Figure 8), connecting the
upper and lower terminal posts on
the left and right sides. These
straps must remain in place for
passive connections but must be
removed for all bi-wire
connections.
external shorting straps in place
(see Figure 8), connecting the
upper and lower terminal posts on
the left and right sides. These
straps must remain in place for
passive connections but must be
removed for all bi-wire
connections.
IMPORTANT: If the amplifiers are
connected to the S4800
loudspeakers in the bi-wire mode
with the shorting straps still on, the
amplifier outputs will be shorted,
which could result in costly
amplifier damage when the power
is switched on.
connected to the S4800
loudspeakers in the bi-wire mode
with the shorting straps still on, the
amplifier outputs will be shorted,
which could result in costly
amplifier damage when the power
is switched on.
12
Figure 9.
Removing shorting straps.
(Bi-Wire Connection Method)
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