JBL Ti10K, Инструкция по эксплуатации

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same length. If the cable to one speaker system is longer than the
one to the other speaker due to the distance from the power
amplifier, make sure not to wind the excess cable up in the form of a
coil. Instead, try to arrange it in figures of eight, as this will minimize
the inductance of the cable run and thus minimize cable losses at
high frequencies.
CAUTION: Never connect two amplifiers to the same loudspeaker
without first removing the strapping bars. Operating two amplifier
channels with the bars in place can seriously damage the amplifiers
and void the warranty.
Another option is to power each separate drive unit (and its
associated network section) from its own power amplifier.
Up to four identical stereo power amplifiers may be used, although
specialized amplifiers for low, mid and high frequencies can offer
clear advantages.
Your JBL Ti-dealer can recommend amplifiers that best suit your
needs. In any case, it is important to make sure that the gain of the
individual amplifiers used is identical, or that input level controls are
provided to maintain proper balance between the various sections of
the speaker.
Beware that some power amplifiers invert the polarity of the signal.
Amplifier polarity marking is not always a true indicator. The polarity
of the signal should be the same for all sections of the speaker.
If the polarity is reversed to one section of the loudspeaker, a
discontinuity in the freefield response will be apparent in the cross-
over region. This can change the sound significantly, but will
otherwise do no damage to either the speaker or the amplifier.
AMPLIFIER POWER
RECOMMENDATIONS
The Ti speakers are capable of handling peak power far exceeding
the continuous rating specified for the individual speakers.
The continuous ratings are based on an eight hour test using
broadband noise shaped to simulate the power distribution of
music. The peak rating of approximately 4 times the continuous
rating indicates the system's ability to handle transient peaks well
above the average power levels.
Amplifier power ratings are an INDICATION of how loud the system
will play without distortion. Amplifier power is generally measured
with steady state test signals and perhaps, in addition, dynamic
measurements into resistive loads. Unfortunately none of these are
firm indications of how loud the system will sound in a given
listening room.
For these reasons, an amplifier should only be chosen after careful
listening. If it is possible to achieve the desired volume level without
distortion, then the amplifier has sufficient power regardless of the
rating.
More important than the power rating is the quality of sound the
amplifier is capable of. Unfortunately, amplifier specifications are
not a reliable indicator of sound quality. Your JBL Ti Series dealer
can make recommendations and arrange auditions to aid selection
of suitable amplification.
If the system is set up with separate power amplifiers for high and
low frequency sections, the amplifier for the high frequency section
can be of less power than the amplifier driving the low frequency
section because of the power distribution in recorded music. As an
example: if a 100 watt low frequency amplifier is used, a 50 watt
high frequency amplifier will “run out of power” at approximately the
same level when playing music.
Fuses or circuit breakers of any kind should not be used between
the amplifier and loudspeakers. All such devices will seriously
degrade the sound quality and do not ensure protection from
loudspeaker damage. The key to safe operation is adequate
amplifier power to avoid distortion at the highest sound levels
required.
GENERAL CARE
JBL Ti Series loudspeaker systems are finished in select wood
veneers. The veneer is protected with a coating that will retain its
finish for many years to come. Occasional cleaning with a clean, soft
cloth will maintain the original beauty of the finish.
The beautiful deep gloss finish is the result of a meticulous multi-
step painting and polishing procedure. The surface should be
treated very carefully to avoid scratching the finish. Only lint-free
cotton cloths should be used for dusting. To remove fingerprints and
smudges, an ammonia-free window cleaner may be used. Apply a
small amount to a lint-free cotton cloth and gently clean the surface.
Never use any abrasive cleaners or strong chemical to clean the
enclosure. In case of deep scratches or damage, please consult a
qualified furniture repair shop.
GRILLE
The grille is held in place by a pin located at each corner. To
remove the grille, grasp two corners and gently pull the grille away
from the enclosure. To replace the grille, position the mounting pins
on the cups and gently press until the grille meets the enclosure.
Although the grille has been engineered to minimize acoustical
interference, high frequency response and stereo imaging will be
improved by removing the grille.
Any dust on the grille should be removed using a cleaning brush or
a vacuum cleaner.