Lightning Audio S2.200 - USING PASSIVE CROSSOVERS; Crossover Functionality and Impedance

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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 2Ω stereo and 4Ω bridged
(mono) loads.
6dB/Octave Low-Pass
6dB/Octave High-Pass
Freq.
Hertz
Speaker Impedance
80 4.1mH 1000µF 8.2mH 500µF 16mH 250µF
100 3.1mH 800
µF 6.2mH 400µF 12mH 200µF
130 2.4mH 600
µF 4.7mH 300µF 10mH 150µF
200 1.6mH 400
µF 3.3mH 200µF 6.8mH 100µF
260 1.2mH 300
µF 2.4mH 150µF 4.7mH 75µF
400 .8mH 200
µF 1.6mH 100µF 3.3mH 50µF
600 .5mH 136
µF 1.0mH 68µF 2.0mH 33µF
800 .41mH 100
µF .82mH 50µF 1.6mH 26µF
1000 .31mH 78
µF .62mH 39µF 1.2mH 20µF
1200 .25mH 66µF .51mH 33µF 1.0mH 16µF
1800 .16mH 44
µF .33mH 22µF .68mH 10µF
4000 .08mH 20
µF .16mH 10µF .33mH 5µF
6000 51
µH14µF .10mH 6.8µF .20mH 3.3µF
9000 34µH 9.5µF68µH 4.7µF .15mH 2.2µF
12000 25
µH 6.6µF51µH 3.3µF 100µH 1.6µF
2 OHMS
8 OHMS
4 OHMS
L
C L
C
L C
L
C
L = Low-Pass (Inductor)
C = High-Pass (Capacitor)
For more information, see your Authorized Lightning Audio Dealer.