文档介绍：Wireless World, April 1969
Simple Class A Amplifier
A 10-W design giving subjectively better results than class B
transistor amplifiers
by J. L. Linsley Hood, .
During the past few years a number of excellent designs have been published for domestic audio
amplifiers. However, some of these designs are now rendered obsolescent by changes in the availability
ponents, and others are intended to provide levels of power output which are in excess of the
requirements of a normal living room. Also, most designs have tended to be plex.
In the circumstances it seemed worth while to consider just how simple a design could be made which
would give adequate output power together with a standard of performance which was beyond reproach,
and this study has resulted in the present design.
Output power and distortion
In view of the enormous popularity of the Mullard "5-10" valve amplifier, it appeared that a 10-watt output
would be adequate for normal use; indeed when two such amplifiers are used as a stereo pair, the total
sound output at full power can be quite astonishing using reasonably sensitive speakers.
The original harmonic distortion standards for audio amplifiers were laid down by D. T. N. Williamson in a
series of articles published in Wireless World in 1947 and 1949; and the standard, proposed by him, for
less than