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What is APC ?
APC is one of the most intelligent amplifier protection circuits ever designed, simply
because it does the job without interfering with the typical dynamic character of
music. APC allows you to fully exploit the potential of the amplifier, maintaining high
power reserves and thus producing high, clean power.
It is a common misunderstanding that high power amplifiers will overload or destroy
lower power speakers, the opposite is true. You can easily destroy a 500 Watt rated
speaker with a simple 50 watt power amplifier ! Why ? In order to produce a low tone,
such as a kick drum or bass guitar, you need about 80 % or more of an amplifier’s
power. Because distortion is less audible in low frequencies, you would want to
increase the level more than the amplifier can supply. This causes low frequency
distortion which causes high frequency harmonics. These harmonics contain more
high frequency energy than the high frequency speaker can deal with. Result: harsh
distortion and sudden heat rise in the high frequency speaker’s voice coil. After a
short while, the high power speaker may burn out.
Conclusion: don’t punish your speakers with weak amplifiers. Set the APC control
to a power level equal to your speaker’s RMS input power and avoid hitting the clip
limiter !
