JBL S4800, Руководство пользователя

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In all cases, the left and right
amplifiers for each section must be
identical. Make sure that the input
sensitivity of the amplifier for each
section is equal, or that input level
controls are provided to maintain
the proper low-to-mid/high bal-
ance. If two identical stereo ampli-
fiers are used, one may be located
near each loudspeaker and drive
low- and high-frequency sections
through short wire runs.
NOTE: Input polarity must be the
same for both the low- and high-
frequency sections. Some ampli-
fiers invert polarity. If the polarity is
reversed to one section, a discon-
tinuity in response will be apparent
in the crossover region. If a prob-
lem is suspected, reverse the
polarity to either low- or high-
frequency sections of both
loudspeakers. Amplifier polarity
markings may not ensure correct
polarity connections.
THE WOOFER GRILLE
Grilles on the S4800 loudspeaker
system have been designed for
maximum acoustical transparency.
For the most critical listening, how-
ever, JBL suggests removing the
grilles. The grilles are connected
by four pins inserted into four
holes on the face of the cabinet.
To remove each grille, hold the
grille edges with your fingers and
gently pull the grille away. Do not
use any tools to pry the grille off –
this will damage the finish of the
cabinet. To replace the grille, posi-
tion the mounting pins over the
holes and gently press until the
grille meets the enclosure.
FINAL CHECKLIST
• Connect and plug in all other
system electronics.
• Check all connections. If bi-
wiring, make sure both shorting
straps are removed.
• Make sure the HF Trim Switch
2
is correctly set.
The system is now ready for use.
The S4800 speaker system is fully
functional as soon as it is set up.
The amplifier power should not
exceed 300 watts (RMS). There
may be some subtle tonal changes
in bass output over the first week
to 10 days of operation. These are
caused as the movement of the
low-frequency drivers becomes
more fluid and the parts settle in.
This process is completely normal
with transducers of this caliber.
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Figure 12. Connecting speaker wires using
bare-wire method.
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