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Analog Electronics
tweeter, or bass, middle and treble reproducer.
Figure 4.12 shows a very simple two-way crossover
network. The low-pass filter for the woofer and the
high-pass filter to keep bass out of the tweeter each
cut off at an ultimate attenuation rate of only
6dB/octave. This is barely adequate in practice,
where 12 or sometimes 18 dB/octave would be
used, but it shows the principle. Note that the
arrangement is a constant resistance network, so
that the amplifier sees a purely resistive load of its
rated value, at all frequencies - or would if the
loudspeaker impedance were constant.
In practice the impedance of a loudspeake ...