[Part 1 looks at advantages and disadvantages of different power
supply technologies as well as the design considerations
involved in choosing and evaluating a mains transformer. Part 2
considers the pros and cons of external supplies, inrush current
control, RF emissions from bridge rectifiers, and relay
supplies.] Power-Supply Rail Rejection in Amplifiers The
literature on power amplifiers frequently discusses the
importance of power-supply rejection in audio amplifiers,
particularly in reference to its possible effects on distortion
! I have (I hope) shown in earlier chapters that regulated power
supplies are just not necessary for an exemplary THD
performance. I want to confirm this by examining just how
supply-rail disturbances insinuate themselves into an amplifier
output, and the ways in which this rail injection can be
effectively eliminated. My aim is not just the production of
hum-free amplifiers, but also to show that there is nothing
inherently mysterious in power-supply effects, no matter what su