PowerBass XTA 4000D, Руководство пользователя

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SUB SONIC Filter Adjustment
The sub sonic control (fig.10) will filter out all frequencies below where the
control is set from going to your subwoofer(s). This will prevent your subs
from playing any low frequencies that may harm the speaker. When this am-
plifier is used with a Vented Woofer application it is important to set the filter
frequency at a frequency point 1/2 octave below the vent frequency. This will
prevent the woofer from becoming unloaded by bass frequencies which are
to low for the vented woofer. Once the woofer is unloaded it is operating as
a free air driver and may experience damage by striking the back plate or by
shearing off the spider. Setting the Sub Sonic filter is CRITICAL!
PHASE Adjustment
This control (fig. 9) helps to align the phase shift of a subwoofer for a smooth
blending, without canceling the bass from other speakers or subwoofer(s).
This can be extremely useful since some interior dimensions of certain ve-
hicles can create “dead spots” (cancellations) affecting low bass and mid
bass impact.
Fig.10 Sub Sonic Adjustment
Fig.9 Phase Control
LPF (Low Pass Filter) Adjustment
The crossover frequency adjustment (fig. 8) filters out frequencies that you
don’t want your speaker(s) to reproduce. Using the LPF control, adjust the
Low Pass Frequency to limit the amount of mid range you want going to
your woofer(s). Since musical tastes vary, adjust the crossover by ear while
listening to the music of your choice. Be sure to set the tone controls of your
source unit to flat before adjusting the crossover.
Fig.8 Low Pass Control
BASS EQ Adjustment
This special feature is designed to provide you boost at 45Hz, and it allows
you to boost the real Bass EQ up to +18dB. Keep in mind that more is not
always better. Setting the control (fig. 7) to the max (18dB) will stress the
amplifier and the speakers and could result in damage.
Fig.7 Bass EQ Control
15Hz 50Hz
SUB SONIC
50Hz 250Hz
LPF
0˚ 180˚
PHASE
0dB 18dB
BASS EQ