Crossover System; Using The Crossovers - Rockford Fosgate POWER 650 MOSFET Owner's Manual

CROSSOVER SYSTEM

The Power 650 MOSFET incorporates separate high- and low-
frequency crossovers,
switches on one end of the power amplifier. The crossover
frequency is set to one of five frequencies or to flat response,
depending on speaker
The crossover is a two-pole (12 dB/Octave)
design with a Butterworth
designed for an accurate phase match between low- and high-
frequency outputs (within 5 degrees) to reduce cancellation and
lobing errors.
High-Frequency
Crossover
Position Frequency
1 Flat
2 140 Hz
3 200 Hz
4 280 Hz
5 400 Hz
6 560 Hz

USING THE CROSSOVERS

The crossover system in the 650 MOSFET is designed to
combine the option of flat system response with flexible
biamplified system
The FLat position of the crossover should be used when a
channel pair is driving a high-power full-range speaker load.
Light-duty "full-range" speakers will probably not 'handle full
bass power and should be connected to the high-channel
amplifiers. Then the high-frequency crossover can be set to
reduce the low-frequency drive. (It is doubtful that any 4-inch
speaker can handle the power of a 650 MOSFET at a lower cutoff
than 280 Hertz, for example.)
The Flat position of both the high and low-frequency crossovers
must be used when the speakers are connected in the Bridged
Stereo mode. In Bridged Stereo, the Left High and Left Low
channels (for instance) are both connected to a single speaker
system, so both Left channels need the same full-range drive.
which are controlled
and system
transfer characteristic.
Position
1
2
3
4
5
6
crossover points.
-9-
by screwdriver-slot
characteristics.
constant-power
Outputs
Low Frequency
Crossover
Frequency
Flat
70 Hz
100 Hz
140 Hz
200 Hz
280 Hz
are