It isn't important what this product is that the image is taken from. Could be anything. Let's focus instead on how the example looks at the beginning of the square wave. See the little "tit" or rise at the beginning? The little sharp edge? This will tend to sound a little bright when you have this rise. You see this type of imperfection when you use feedback. You can see it in other situations as well, but when it's a result of feedback, there are sonic consequences.
I am sure the technocrats will howl over this, but I am simply sharing with you some years of experience. If this tack-sharp blip is present in an amplification stage with GNFB (global negative feedback), almost invariably the amp will have a hard or slightly bright sound indicative of that type of topology. Yes, a designer can add a capacitor to smooth out the little tit, but that in itself will not help the sound, only the way this looks on the scope. If the tit is present because of feedback, lowering or eliminating the feedback is one surefire way to get better sound. It's also possible to fix the open loop circuit (no GNFB) such that when you close the loop (add back GNFB), the tits aren't present. But that's fodder for another discussion.
This is the kind of stuff you find out over years of looking at scopes and listening to the sound of circuits.
Now take a look at this square wave.
See how nice, rounded and gentle this looks? Compare it to the other one. If you see this type of response on your scope and it's the output of a simple circuit with or without GNFB the audible results will be far nicer sounding (e.g. musical).
This is the stuff we nerds get excited over at work. Is it any wonder I am antsy about listening to the new circuit?
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