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by lutusp 4511 days ago
> It's just that I wouldn't call turning up the volume knob to be part of the "clipping" process, but rather amplifying.

But it is, indeed it's the most common example of clipping in engineering practice. Consider two alternatives -- one in which the amplifier is able to accommodate a great increase in volume without any distortion, and another in which it cannot.

In this image:

http://i.imgur.com/g8txTmC.png

The blue trace represents maximum normal volume (100%). The green trace represents a system in which the amplifier can accommodate a great increase in volume setting (200% of normal), simply because its power supply voltage is at least twice as high as that required for 100% volume. The red trace represents a system that cannot tolerate any volume settings greater than 100%.

In this diagram, the 200%-volume green trace has a higher subjective volume level than the 100%-volume blue trace (i.e. twice as high in voltage, four times as high in speaker power). The red trace, which would sound very distorted to the user, also has a higher power level than the 100% trace, but less than the green trace. The red trace is typical of systems that are limited to 100% volume by power supply voltage.

The red trace represents the most common example of "clipping" as it takes place in actual equipment and in engineering practice. Its output has more energy than the blue trace, and less than the green trace.

-- former NASA engineer

1 comments

I agree with everything you wrote. Again, however, I think we're talking past one another. When you talk about clipping, you seem to mean turning up the volume until a signal clips. This both amplifies the signal and clips off its extremes. What I mean by clipping is to take a signal and clip off its extremes.

That sole difference explains our entire conversation. In your view, clipping involves making the signal bigger. That bigger signals carry more energy naturally leads to your claim. In my view, clipping a signal makes it smaller, leading to the opposite claim.

Thanks for sticking with me through the conversation.