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Slew rate, TIM hogwwash

Posted by gusser on July 6, 2017 at 15:28:24:
Both very fast slew rate and TIM are easily simulated and measurable in any audio amplifier. Just send it fast rise time square waves and thee issues will quickly arise. In the late 1970s TIM was all the rage but few audiophiles understood the engineering behind it and thus the flaw in this measurement.
Nothing in nature can produce an acoustic wave with rise times that fast. Our 15psi atmosphere simply won't allow it. Not to mention there is no microphone or speaker that can move or react that fast. So unless artificially electronically generated, no sound can have a rise time that fast.
Which translates to amplifiers with fast rise times and low TIM are indeed very good engineering designs. But the truth is, it's a useless attribute because no audio amplifier will ever be called upon to reproduce rise times that fast.
Now that's not to say square wave testing is useless. It is very useful and important to test the amplifiers stability. But the ability for an audio amplifier to have rise times in the video range is of no use in reproducing sounds on Earth.