K2S4800 (serv.man2) - JBL Audio User Guide / Operation Manual. Page 11

The S4800 has an 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.

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

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.

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

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.

3 Low-Frequency Input Terminals:
For bi-wire configurations, connect
the speaker wires for the low-
frequency range to these terminals.

11

Figure 8. S4800 controls and connections.