In Reply to: RE: rant warning posted by Tre' on August 27, 2012 at 19:05:04:
As far as the amplifier is concerned, its B+ power supply is just a "black box" with two output terminals, connected to the + and - leads of the PS output capacitor. All that the amplifier "knows" about this black box is that it is supplying a time-dependent voltage V(t) across its two terminals.
The supply voltage is time dependent for a variety of reasons, of which the three principal ones are:
1) 120Hz or 60Hz mains ripple
2) Ripple at audio frequencies, because the PS is part of the audio path
3) Longer-term voltage sag effects caused by extended loading during loud passages.
In an "ideal" power supply, the voltage V(t) would be constant; i.e. independent of time. This would, more or less by definition, lead to the case of "uncolored" sound from the amplifier. Clearly, adding more output capacitance can only have the effect of reducing the amplitude of the time-dependent fluctuations, and thus bringing the black-box power supply closer to the "ideal" case.
If it is asserted that a higher value of output capacitor in the power supply sounds less "musical" than a lower value, and if this can be verified to be a real and reproducible phenomenon and not an imagined one, then this must mean that some deficiency in the power supply (i.e some departure away from a constant-voltage source) actually leads to a coloration of the sound that is more pleasing to the human ear. Maybe, for example, as Triode_Kingdom suggested, some kind of enhancement of an intermodulation distortion.
Designing an amplifier system in which some deficiencies in the power supply are built in for the purpose of enhancing the tonal quality seems to be a somewhat back-to-front approach.
Chris
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Follow Ups
- RE: rant warning - cpotl 08/28/1205:28:43 08/28/12 (0)