Rockford Fosgate FA15.0 - Manual (Page 13)

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* This graph was generated by setting the variable crossover to 40Hz
50Hz, 60Hz, 70Hz, 80Hz, 90Hz, 100Hz, 120Hz & 140Hz.
Auto Turn-on / Sleep Mode
The Fosgate Audionics subwoofers automatically turn on when they sense an input signal. When the
signal being fed to the subwoofer is turned off, the subwoofer’s amplifier will turn off and go into
“sleep mode.” This feature eliminates the inconvenience of operating a mechanical power switch.
Input Sensitivity
The Input Sensitivity is used to match the Point Zero series with signal levels from a variety of signal
sources. The Input Sensitivity uses a potentiometer to match input levels over a 30dB range and is
variable from 0dB to -30dB. The numbers listed on the back panel indicate attenuation from maxi-
mum gain, calibrated in dB.
Low-Pass Crossover
The Low-Pass Crossover is used to set the electrical cutoff point of the subwoofer enclosure. The
Crossover uses a variable potentiometer to set the cutoff point anywhere between 40Hz and 140Hz.
When the control is set to its full CLOCKWISE posi-
tion the cutoff frequency is set to 140Hz Low-Pass.
When the control is set to its full COUNTER CLOCK-
WISE position the cutoff frequency is set to 40Hz
Low-Pass.
It is important to match the Low-Pass crossover point
of the subwoofer with the High-Pass crossover point
of the high frequency reference monitors.
Mismatching the crossover points can cause dips or
peaks in the acoustical response. Overlapping the
crossover points (i.e., subwoofer at 60Hz Low-Pass &
high frequency monitors at 50Hz High-Pass) can
cause a peak between 50Hz and 60Hz.
Underlapping the crossover points (i.e., subwoofer at
40Hz Low-Pass & high frequency monitors at 70Hz
High-Pass) will cause a dip between 40Hz and 70Hz.
We recommend using a crossover setting whenever
possible to minimize “localization” of the subwoofer,
usually between 50Hz and 60Hz. These low frequen-
cies make it nearly impossible to detect where the
subwoofer is in the listening room.
Operation
Electrical Crossover Response*
50
60
70 80
90
100
120
140
40HZ
Low Pass
50
60
70 80
90
100
120
140
40HZ
Low Pass