QSC KW181, Руководство пользователя

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EN
High-frequency EQ
On the KW122, KW152 and KW153 there are two high-frequency settings. From the factory, the
switch is set to FLAT. This means that the loudspeaker system is producing a flat response through
the vocal band. This is the standard setting for most applications.
In voice-only reproduction, the switch can be set to the VOCAL BOOST setting. This will engage EQ
that gives a stronger presence for vocal intelligibility and presence. It is generally not recommended
to use this setting when playing full-range music through the system.
Subwoofer Polarity
Polarity (sometimes improperly referred to as phase) refers to the voltage of an input signal and
whether it is a positive or negative voltage at any given time. In most cases a positive voltage
causes a woofer cone to move forward with respect to the cabinet orientation, and a negative
voltage then moves the woofer cone backward. Most importantly, speakers reproducing the same
signal or signals that are adjacent in frequency must have the same polarity to get the maximum
output. This is most important for low frequencies. Polarity can be altered by incorrect wiring or
mixer control settings.
The KW181 provides a polarity switch to correct any wiring or mixer setting errors. The polarity
switch is set in the NORMAL position from the factory.
When using the KW181 with KW Series full range loudspeakers, NORMAL polarity will result in the
best bass response if the full range loudspeakers are sitting on or very close to the subwoofers. If
the subwoofers are some distance away from the full range loudspeakers, polarity change may be
of benefit. Start with all subwoofer POLARITY switches in the NORMAL position. Then, with the
system at or near expected operating levels, change the polarity of each subwoofer
individually .
Walk around the venue and assess the overall bass response. Select the polarity that results in the
best overall system bass response.
When using only one KW181 and connecting a LEFT and RIGHT stereo signal, start with the polarity switch in the NORMAL position. With the system
at a reasonable level, change the POLARITY switch and evaluate which polarity results in the most low-frequency output.
KW122, KW152, KW153 High-frequency
EQ Switch
KW181 Polarity Reversal Switch