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drastically attenuated. The result would be indistinct speech and
boomy music. Even with a Q as low as 100, 30%, or 3 dB, of 5 kHz
modulation would be lost, but this would not be too much to restore
by an equaliser (Sec. 19.3).
Because the effective frequency bandwidth for a given Q is
proportional to the carrier frequency, whereas the bandwidth
required is unaffected by it, the sideband cutting effect is less at
higher carrier frequencies and greater at lower carrier frequencies.
With frequency modulation there is the same need to preserve
sidebands, but the results of failing to do so are different. Fig. 15.7
might certainly suggest tha ...