ieLogical is my domain.
I used an espresso machine precisely because it is a resistor and a near constant load. I wasn't testing the dynamic headroom of an amp. That is a property of the amplifier and not the line. I could run the identical test on my HiFi, but it's much more of a PITA. Additionally, amplifier peak output has the inconvenient habit of occurring when the A/C line is not at peak, so the line cruises merrily along unperturbed. BTDT.
So assuming the transpistors are full on and running off the transformer because the caps are flat, which they never are, instead of 40V at the speaker, there will be 39V. 20log(39/40) = -0.22db <OUCH!>
When the load current drops as the signal alternates phase, the draw from the capacitors decrease and the capacitors charge. If the load amplitude peaks when the line is 0v,all the current is supplied by the capacitors.
Please have a look at http://ielogical.com/assets/CblSnkOil/HFoverLine.png to see what is happening with high frequency and the line. The capacitors supply ALL the power when the transformed voltage is below the capacitor voltage + the diode drop.
I used an espresso machine precisely because it is a resistor and a near constant load. I wasn't testing the dynamic headroom of an amp. That is a property of the amplifier and not the line. I could run the identical test on my HiFi, but it's much more of a PITA. Additionally, amplifier peak output has the inconvenient habit of occurring when the A/C line is not at peak, so the line cruises merrily along unperturbed. BTDT.
3.79V VD What’s that going to do to the power supply of a power amp as the caps are trying to recharge?A 200w power amp is going transform that down to about 2V on the caps. 10ga is going to give +1V more on the caps @ 14A line draw
So assuming the transpistors are full on and running off the transformer because the caps are flat, which they never are, instead of 40V at the speaker, there will be 39V. 20log(39/40) = -0.22db <OUCH!>
There might be only a few microseconds or milliseconds that this can happen, and quite a bit of current might have to flow during that time, essentially a high frequency event.The line provides 60Hz. Full stop. It does not know diddly about any other frequency, distortion components aside. The power supply provides DC. The control devices modulate that DC to provide the AC to the speaker.
When the load current drops as the signal alternates phase, the draw from the capacitors decrease and the capacitors charge. If the load amplitude peaks when the line is 0v,all the current is supplied by the capacitors.
Please have a look at http://ielogical.com/assets/CblSnkOil/HFoverLine.png to see what is happening with high frequency and the line. The capacitors supply ALL the power when the transformed voltage is below the capacitor voltage + the diode drop.