Is the overshoot the square wave generator or the sinc interpolation on the Pico?
Hi John, I have digged out my good old and retired analog scope. Unfortunately, even that one is not fast enough.
And what does this have to do with audio?
for 4K video with speeds up to 12 Gigahertz sure, but audio?
The extremely sharp edge on the square wave is simply not needed for analog audio signals. High speed D1G1T0L [sic] signals would need that, however. The sharpness of the edge shown in the image above is much sharper, or closer to vertical than a 20kHZ upper limit audio signal would need. All an edge that steep will do is make life difficult for linear or switch-mode amplifiers trying to reproduce it, and no speaker would even think of trying to do so.
From a limited view of an usual audio user and consumer, you seem to be right. However, in a design and test phase, the fast generator and fast measurements are absolutely necessary. Below just 2 examples.
1)
Preamp oscillations, at about 4MHz (still low frequency). The occurrence of oscillations was irregular and appeared occasionally during connection of input or output cables when the preamp was on, as a result of fast ESD discharge. Fast step was a way to test it.
2)
Irregular oscillations in output diamond buffer of the preamp,
at 253MHz. This was extremely difficult to find and the only effect in the audio band was THD rising from 0.001% to some 0.02% and rising modulation of noise floor at frequencies below 1kHz, together with a slightly audible LF hum.
I understand that a common user can hardly imagine such scenarios, but the laughter based on limited knowledge is not appreciated. You guys might have had some respect to those who do a real job, this is not addressed to only the posters I am reacting at. It is much better to try to learn than to argue based on limited understanding.
