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power cables - not in the signal path?

According to popular wisdom the AC power is not in the signal path and therefore a power cord, AC conditioner or similar should have zero audible effect.

In a don quixotesque attempt I'd like to turn this perception around: the AC is 100% in the signal path - more so that the actual low-level signal that gets amplified, and I think I found the simple words to clarify this.

The low-level signal is actually only modulating the high-voltage (high-intensity) signal produced by the transformer. Those electrons from the transformer are the actual electrons we "hear". The low-level signal is simply lost in translation. In a simple example, a 0.1V peak-to-peak sine signal gets amplified (say) 10x by a 10 V continuous (transformed) DC. The output is (say) a 1V sinusoid oscillating back and forth in time. If the 10V continuous is NOT actually exactly 10V (but is actually has noise) - then the noise will directly reappear "riding" on the 1V output.

Hence the need to keep the AC noise-free.

(Of course I purposefully neglected for simplicity the other effects (need for instantaneous delivery of power, etc..) for which I did not find a simple enough description (without reference to I/V curves and impedance / capacitance details, that is).

Does is make sense?

Thanks
C.
cbozdog
zd542
5,339 posts
 
Would this be a good way to visualize it?

Think of a car as an audio system and the road represents your power/electricity. The car/audio system has a level of maximum performance it can achieve. But you can only get the best performance if you drive on a very good road. If you drive on a road that is in bad condition, you can't drive the car to its fullest potential. So even though the electricity going through the power cables in not part of the signal path, it can still effect it.
cbozdog OP
63 posts
 
Eh - sure the original post is oversimplification. Not doubting the other effects that are meant to improve the (former) AC signal, i neglect them in order to keep it easy to follow. All conversion, filtering and capacitive storage aside - the low-level signal does nothing more than opening and closing (I e modulating) the passage of a huge amount of electrons (obtained from the AC originally) through the device. It is not the low-level signal electrons that eventually get heard. if anything, it is the latter electrons that passed through the floodgate that eventually reach the audio transducer, etc.

I do stand corrected though regarding complexity - surely all amp designers make provisions to have a time-invariant pool (DC) to draw from. Maintaining such pool is hard though (is probably what separates boys from men).

No substance abuse here - sorry C.
stevecham
3,340 posts
 
EVERYTHING IS IN THE SIGNAL PATH
rodman99999
6,035 posts
 
I've found power supply mods to make major audible improvements in whatever audio device applied(tubed, SS, analog, digital, all of my own and quite a few happy customers), for a few decades. The new breed of PCs and fuses have seemed to me, the icing on the cake. My take on the function of power supplies and gain stages/output devices was reinforced by Viktor Khomenko, in an interview with Stereophile, some years back(made me feel quite good). Couldn't find that interview(online), but it was partially echoed here: (http://www.theabsolutesound.com/articles/balanced-audio-technology-vk-600m-se-monoblock-power-amplifier-1/)
czarivey
5,754 posts
 
C, It's entertaining indeed! I should read it again and than few more times when I get home and get stoned.
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