good discussion on power cords

The minimum gauge will be 18. It absolutely will not be 20 or 22. For the JA800 based on current draw, it will be 16 or 14 minimum. Most companies will at least meet the basic electrical code requirements even if they don't get proper safety certification.

You can disagree but I get the impression you are not technically qualified to do any more than "disagree".  No they are not "all related". A primary purpose of the power supply in an amplifier is to isolated completely the AC from its impact on the audio signal.


Rectification is the electrical function, modulation is the signal processing operation that occurs. The rectification is a signal processing multiplication function, or modulation. Ideally you would only modulate the 60Hz AC with only 60Hz to yield 0Hz = DC, but the modulation function ends up being something more akin to a pulse (rectangular waveform) multiplied by a sine wave, hence you end up with all kinds of harmonics of 120Hz that you need the capacitors to filter out. Ideally you design your power supply with inductive filters to extend that "pulse" and reduce those high frequency harmonics to there is less ripple for the capacitors to filter.

andy21,171 posts07-05-2020 10:28pm

but I think we can state pretty unequivocally that the goal of the power supply is to isolate the output (audio) from the input as best as possible.

I would disagree with that statement. There is really no "isolation". They are all related.

Technically the diodes in the power supply perform a modulation function on the incoming AC which is why you get DC.

I think that is called "rectificatioin", not "modulation".  

^^^ Well it seems like you're disagreeing with Charles Hanson who is actually a real designer ... sigh ... face palm ...

Your description of rectification and modulate makes me laugh so hard.  I suppose until you understand the difference between "rectification" and "modulation", there is not need to argue with you since it would be a waste of time.  

Why would I not agree with him if he makes a poor analogy? I don't idolize people who made interesting products but didn't contribute to moving the science or art forward.


You laughing at my description of modulation shows you had no clue what I was talking about. No worries people who understand this stuff will know exactly what I mean or will at least know enough to ask the right questions. The joke is on you. Understand frequency domain analysis makes designing power supply filters much easier and the results more successful. That's the difference between tinkering and engineering I guess.

^^^ OK, whatever, so you're a pretty good at copy and paste.