Consider the circuit connection to the AC amplifier with two bridge output channels. Dynamic head BA1, BA2 speakers form the left and right stereo channels. They are shown conventionally broadband. Low-frequency head BA3 is connected between the output of the amplifier left and right channels, the signals are summed and head reproduces a mono signal.
This connection will be sure to have two high-pass and low-pass filter for the stereo for the total channel. Their mission - to eliminate the parallel operation and overload amplifier heads. Usually used for stereo first order filters (C1, C2), for the total - the second (C3L1) or third.Their payment is made in the usual way. Crossover frequency of the LPF and the order chosen in the range 80 ... 200 Hz, depending on the location of the low-frequency head. If it is placed in the rear compartment, the crossover frequency should be selected as low as possible, and the order - up to avoid reproducing the subwoofer "voice" of the range. However, this requires the manufacture of relatively large inductors.Used in their construction ferromagnetic yokes undesirable because the distortion caused by the inevitable core magnetization significantly degrade sound quality.
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