Self on Audio, 2nd Edition

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Distortion in power amplifiers, Part VII: frequency compensation and real designs

The distortion performance of an amplifier is determined not only by open loop linearity, but also the negative feedback factor applied when the loop is closed. In most practical circumstances doubling the NFB factor halves the distortion. To date, this series has focused on basic circuit linearity. I have assumed that open loop gain falls at 6 dB/octave due to a single dominant pole, with the amount of NFB permissible at HF being set by the demands of HF stability. Because of this, the distortion residuals from a ‘blameless’ amplifier are comprised almost entirely of crossover artifacts due to their high frequency content. Audio amplifiers using more advanced ...