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Distortion.

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Playing in an old version of Cooledit, an audio editing program, I made a distortion filter with a big notch in the linear transfer function, about 1/4 the away along, to simulate very very extreme crossover distortion (not zero bias crossover distortion but imagine a horrendous notch where one output devices switches off, far FAR worse than what happens in real life). When I say notch, I mean a flat line, so the gain effectively goes to zero for a small portion of the waveform. The waveform in the editor is now visually "chopped" around these parts.

Oddly enough, while the playback is obviously distorted, it's nowhere near as bad as you'd imagine. It doesn't make your ears bleed, there is simply a fuzz over the signal. Playing with less extreme (but still more extreme than in real life) virtual "crossover" distortion is hard to hear. If I make a gross asymmetric transfer function like a really badly designed SE would have the distortion is also not intrusive.

Any sensibly designed no-feedback amp will be much more linear than all this artificial distortion I created

These are my findings, make of them what you will
 
You are absolutely right;
modern rap music is made especially to go through long chains of opamps each of them add small amont of crossover distortions, up to an output amp that is also built like a powerful opamp.

But did you try to listen nice classical music on good speakers that went through your transfer function? Try grand piano with nice reverberation and compare...
 
I did not listen to rap through the transfer function, but yes, I suspect that anything delicate will be tortured somewhat. Oddly enough, the distortion I added actually reminded me of modern recordings a bit! (Things seeming distorted without anything clipping)

I will try it with some piano music.
 
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bigwill said:
Right, I tried with piano music and the smallest notches made horrible noises, and yet with pop a large notch didn't really make THAT much difference.

Old fart nods his head sagely... As Wavebourn suggests, piano is a complete ba$trad - so many failings make it sound like a castrated harpsichord. The quality of modern recording is falling as cheap mixers become more commonplace and heavy compression and inadvertent digital clipping become the norm.
 
OK, with this experimentation I've basically found out for myself what is pretty much well known

Symmetric distortion and even SMALL notches will utterly destroy piano or any delicate sounding music. At first I was fooled into thinking this kind of distortion just added a "switching fuzz" but boy I was wrong.

Large amounts of ASYMMETRIC distortion with smooth nonlinearites are surprisingly benign, even with piano music! If you make it symmetrical however, it sounds pants.

So basically everything needs to be single ended :D
 
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