Using Passive Crossovers - Rockford Fosgate 250.1 Operation & Installation

10. Perform a final check of the completed system wiring to ensure that all connections are accurate. Check all
power and ground connections for frayed wires and loose connections which could cause problems from
road vibrations.
11. After the final inspection is complete, install the power fuse and enjoy listening. During the initial listening
period, you may need to "fine tune" any phasing and level settings within your particular vehicle. To aid in
this procedure, play a track with high musical content and cruise around your neighborhood. After fully
evaluating the transient response of your system and making any final adjustments, all your neighbors within
a 1 mile radius will assume that you have just successfully completed another upgrade to your audio system
for which they will probably spill thumbtacks on your driveway.
U P
SING ASSIVE
A passive crossover is a circuit that uses capacitors and/or coils and is placed on speaker leads between the
amplifier and speaker. The crossover delegates a specific range of frequencies to the speaker for optimum driver
performance. A crossover network can perform one of three functions: High-Pass (capacitors), Low-Pass
(inductors or coils) and Bandpass (combination of capacitor and coil).
The most commonly used passive crossover networks are 6dB/octave systems. These are easy to construct and
require one component per filter. Placing this filter in series with the circuit will reduce power to the speaker
by 6dB/octave above or below the crossover point depending on whether it is a high-pass or low-pass filter. More
complex systems such as 12dB/octave or 18dB/octave can cause impedance problems if not professionally
designed.
Passive crossovers are directly dependent upon the speaker's impedance and component value for accuracy.
When passive crossover components are used in multiple speaker systems, the crossover's effect on the overall
impedance should be taken into consideration along with the speaker's impedance when determining amplifier
loads.
Amplifiers using the trans• nova topology improve in sound quality after
warming up. We recommend operating the 250.
mately 15 minutes prior to evaluation under judging criteria or tune-ups to
establish its normal operating temperature.
* Your friends will call it MAGIC, you can call it Rockford technology! *
C
ROSSOVERS
NOTICE!
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