K2S4800 (serv.man2) - JBL Audio User Guide / Operation Manual. Page 10

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.

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.

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.

CAUTION: The S4800  is a massive
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.

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 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.

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

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.

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.

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.

Figure 7. 

Room placement of S4800 speaker system.

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