McIntosh MC252 - Manual (Page 16)

16
Technical Description
McIntosh Laboratory, the company who introduced the
world’s first amplifier that could be called “High Fidelity”,
has done it again. The McIntosh engineering staff has cre-
ated a power amplifier without compromise, using the most
advanced McIntosh circuit design concepts.
A continuous average power output rating of 250 watts
and with an output current of greater than 50 amperes per
channel, making this one of the most advanced and power-
ful amplifiers McIntosh has ever manufactured. The distor-
tion limits for the MC252 are no more than 0.005% at rated
power output for all frequencies from 20Hz to 20,000Hz.
Typical performance at mid frequencies is less than
0.002%. The true distortion readings on the MC252 are so
low, it takes special measuring techniques to make accurate
readings. The MC252 can deliver the best possible perfor-
mance from any type of high quality loudspeaker system.
Creating an amplifier with this level of performance did
not come easily. Many months of design, testing and mea-
suring were required. Extensive controlled listening tests,
the ultimate form of measuring, were made before the final
design was accepted.
Design Philosophy
The design philosophy incorporated in the MC252 in-
volved several different techniques, all based on sound sci-
entific logic. Refer to figure 14. Every stage of voltage or
current amplification must be as linear as possible prior to
the use of negative feedback. McIntosh engineers know
how to properly design negative feedback circuits so they
contribute to the extremely low distortion performance ex-
pected from a McIntosh amplifier. The typical McIntosh
owner would never accept the approximately 100 times
higher distortion of many non-feedback designs.
All transistors are selected to have nearly constant cur-
Inside View of the MC252