Lc c c, Installation, Speaker impedance – Lightning Audio FF150.2 User Manual
Page 7
7
Installation
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: The Lightning Audio amplifiers are not recommended for impedance
loads below 2
Ω stereo and 4Ω bridged (mono) loads.
80
4.1mH 1000µF
8.2mH
500µF
16mH
250µF
100
3.1mH
800µF
6.2mH
400µF
12mH
200µF
130
2.4mH
600µF
4.7mH
300µF
10mH
150µF
200
1.6mH
400µF
3.3mH
200µF
6.8mH
100µF
260
1.2mH
300µF
2.4mH
150µF
4.7mH
75µF
400
.8mH
200µF
1.6mH
100µF
3.3mH
50µF
600
.5mH
136µF
1.0mH
68µF
2.0mH
33µF
800
.41mH
100µF
.82mH
50µF
1.6mH
26µF
1000
.31mH
78µF
.62mH
39µF
1.2mH
20µF
1200
.25mH
66µF
.51mH
33µF
1.0mH
16µF
1800
.16mH
44µF
.33mH
22µF
.68mH
10µF
4000
.08mH
20µF
.16mH
10µF
.33mH
5µF
6000
51mH
14µF
.10mH
6.8µF
.20mH
3.3µF
9000
34mH
9.5µF
68mH
4.7µF
.15mH
2.2µF
12000
25mH
6.6µF
51mH
3.3µF 100mH
1.6µF
Freq.
Hertz
Speaker Impedance
2 OHMS
8 OHMS
4 OHMS
L
L
L
C
C
C
6dB/Octave Low-Pass
6dB/Octave High-Pass
L
C
L = Low-Pass (Inductor)
C = High-Pass (Capacitor)
For more information, see your
Authorized Lightning Audio
Dealer.
!