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RE: How to reproduce the full dynamics of a scissor cutting paper without clipping

No, you do not understand.

As opposed to measured SPL, Subjective loudness is not only level dependent but also frequency dependent (as the equal loudness curves show) and relevant to this discussion also Time dependent where short sounds are not perceived as loud as the SAME ACTUAL SPL for a longer duration.

In the examples I gave, I WAS holding the meter and my ears were approximately the same distance away from the source, those levels were the instantaneous peak values and even if it had been set to "Fast", the meter would never have reached anywhere near that value.

Maybe this will be clearer. Microphones have a pressure sensitivity figure, if you measure the voltage coming out of one, one can calculate the pressure that caused that Voltage. Vu meters, SPL meters (generally) do this conversion and give a display but these have significant integration times, more like our ears.

If one examines the microphone voltage with an oscilloscope, one can capture the peak voltage any event produces and these peak pressures for many sounds are far greater than the average level over say a fraction of a second or longer.
Now, I have never measured a key in a lock or scissors but a reoccurring them with household sounds and percussive instruments was that the peak levels were often surprisingly high compared to what a normal "fast" SPL meter showed.

The best part, you don't have to take my word for it, anyone with some modest testing ability can make the same kind of tests and see for themselves what sounds are really like, what is really required and not just the part that is convenient to reproduce that at best only reminds you of a real event..

Possibly the biggest thief of subjective dynamic range (aside from the recording end) is instantaneous clipping which unlike prolonged clipping is inaudible as a flaw and only apparent when you compare with and without it. Here too an oscilloscope looking at your power amplifier output (fast triggered sweep) will show if there is clipping at any stage up to there.


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