Re: Audiophoolery?
Yes indeed - the velocity factor is in the range 60-80% the speed of light for most common cable constructions, and you can consider audio cables to be in that sort of range. It is not at all relevant to most aspects of audio cables (but not all - it depends on the frequency, which for RF interference needs to be considered)
The peak charging currents can be tens of amps on the rectifiers and transformer secondaries when the associated amp is being worked hard, or on transients longer than a mains cycle. But the turns ratio, for a transistor amplifier in the range of 8:1, so the primary current pulses are much less - but could get to surge peaks of a few amps. Generally the rear chassis fuse on a power amp is usually something like 6.3A slow blow for that reason.
That is why quite a few amplifiers now use power factor corrected switched mode supplies to cut down on the high current surges from conventional supplies, which can give issues in meeting conducted EMC specs necessary as part of the CE marking test programme.
Craig
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