Rockford Fosgate 250.2 - Manual (Page 15)

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ROSSOVERS
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.
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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.
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NOTICE!
Amplifiers using the trans• nova topology improve in sound quality after
warming up. We recommend operating the 250. 2 and 250. 1 for approximately
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! *