Using Passive Crossovers - Rockford Fosgate PUNCH 301M Installation Et Fonctionnement

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.
NOTE: Follow the diagrams for proper signal polarity.
CAUTION: These amplifiers are not recommended for impedance loads below 2Ω.
!

USING PASSIVE CROSSOVERS

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.
CAUTION: These amplifiers
!
are not
recommended for
impedance loads
below 2Ω.
L
6dB/Octave Low-Pass
Speaker Impedance
Freq.
2 OHMS
Hertz
L C
80 4.1mH 1000µF
100 3.1mH 800µF
130 2.4mH 600µF
200 1.6mH 400µF
260 1.2mH 300µF
400 .8mH 301µF
600 .5mH 136µF
800 .41mH 100µF
1000 .31mH 78µF
1200 .25mH 66µF
1800 .16mH 44µF
4000 .08mH 20µF
6000 51mH 14µF
9000 34mH 9.5µF
12000 25mH 6.6µF
L = Low-Pass (Inductor)
C = High-Pass (Capacitor)
For more information, see your Authorized Rockford
C
6dB/Octave High-Pass
4 OHMS
L C
8.2mH 500µF
6.2mH 400µF
4.7mH 300µF
3.3mH 301µF
2.4mH 150µF
1.6mH 100µF
1.0mH 68µF
.82mH 50µF
.62mH 39µF
.51mH 33µF
.33mH 22µF
.16mH 10µF
.10mH 6.8µF
68mH 4.7µF
51mH 3.3µF 100mH
Fosgate Dealer.
I
NSTALLATION
8 OHMS
L C
16mH 210µF
12mH 301µF
10mH 150µF
6.8mH 100µF
4.7mH 75µF
3.3mH 50µF
2.0mH 33µF
1.6mH 26µF
1.2mH 20µF
1.0mH 16µF
.68mH 10µF
.33mH 5µF
.20mH 3.3µF
.15mH 2.2µF
1.6µF
7