is it possible to split the common ground of pc headphone OUT into separate grounds with resistors?

realflow100 said:

I have some questions about reverse breakdown voltage of a transistor. should I make a new thread? so not to clutter this one?

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Make a new thread with a schematic that shows what causes the reverse voltage.

audioguru said:

Did you know that "peak power" or "maximum power" is actually double the instantaneous RMS power?

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Actually, the peak power is 1.6 times the RMS power. But "RMS power" is not a meaningful measurement.

You probably mean that peak power is double the average power, which is obvious from the name, since the instantaneous power waveform is a sine wave that goes between 0 and the peak power, so the time average is just half of the peak.

https://www.eznec.com/Amateur/RMS_Power.pdf
https://www.hifi-writer.com/he/misc/rmspower.htm
https://www.n4lcd.com/RMS.pdf

"Music Power" is instantaneous power before the power supply voltage sags from a longer duration tone. Then Peak or Maximum power is a multiple of the Music power. True power or Average power is a continuous tone.
I think of double the power as the difference between a sinewave and a squarewave where both have the same amplitude because many companies advertise their speakers and amplifiers with a horrible-sounding squarewave so that the power number is double the real number.

Meyer Sound agrees with me:
"Making Sense of Amplifier Power Ratings

When an amplifier is rated in RMS watts, this is a shorthand way of saying “average watts obtained by the RMS method.” If you use a signal other than a sine wave, you must use a meter reading ‘true’ RMS voltage to obtain the correct average power.
So what about peak power? Peak power is a special case where Ppeak = Epeak * I peak. For a sine wave, this is always twice the average power."

Peak power is the peak of the power waveform. Average power is the time average of the power waveform:



(and "RMS power" is the RMS value of the power waveform, though that's a nonsensical measurement)

(See also peak-to-average power ratio PAPR.)

If you want to talk about an amplifier's ability to remove heat buildup or hold up its voltage rails, that's a separate issue, "peak" has nothing to do with it. That's "continuous" vs "momentary".

audioguru said:

True power or Average power is a continuous tone.

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When the FTC says "continuous average sine wave power", the "continuous" refers to the long-term tone, and the "average" refers to the time average of the power waveform, as opposed to the peak of the power waveform.

Continuous means the amp is running continuously with the same signal, and any thermal limiting, voltage sag, etc has already happened, and then you measure the average power at some % THD.

You could just as easily measure the "continuous sine wave peak power", which would be measured under the same conditions but would be the peak of the power waveform and would not need an accompanying THD measurement (because it's the same number no matter how much the sine wave is clipped). Peak power is close to twice the average power (depending on the THD of the average power measurement).

Or you could measure the "momentary average sine wave power" or "momentary peak sine wave power", with a burst of sine wave that doesn't allow the supply caps to droop or the heat to build up.

audioguru said:

because many companies advertise their speakers and amplifiers with a horrible-sounding squarewave so that the power number is double the real number.

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I think it has more to do with what the competition is advertising than any actual measurement.