@georgehifi george do you know anything about all the differnent GaN devices used in Technics, AGD, Merrill, and your beloved eval board from EPC? Only one manufacturer uses GaN devices purposed for Audio, do you know which one?
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If you believe this is the actual phase shift of the output of an IcePower based amplifier, can you explain this near perfect 1KHz square wave?
If you have that much phase shift at 1KHz and changing considerably over the harmonics of a 1KHz square wave, then there is no way the wave would look square.
Perhaps there are holes in your knowledge that prevents your understanding of how these things work .....
I know I'm not the brightest bulb in the lamp but what exactly does that phase shift mean in the link from George?
Phase shift is interpreted by the ear as a tonality depending on what is causing the phase shift- a rolloff at high frequency outside the audio band can sound like a darkness, it can also sound like a brightness if there is a peak. The ear uses phase information for echo location, so it can alter the soundstage too. The ear is entirely insensitive to phase at a single frequency, like a sine wave or the like; and there are other factors it uses to sense tonality and soundstage, so even though phase shift plays a role, its not the only way the ear works. But if you really want to get the tonality and soundstage right, this is a thing that needs attention.
While some class D amps have significant phase shift, others do not, just as in traditional amplifier technology. It is a logical fallacy called 'Guilt by Association' that is being employed here by George- he is saying *all* class D amps have this phase shift in the link he provides, when actually the curve is for a very specific amplifier. Logical fallacies are inherently false and this is an excellent example.
Thanks, I've been reading a bit on phase shift or angle, same thing ?? Still trying to digest it, from one article it appears they're saying not to worry to much about it in an amp.
In one sense, you can consider the effects of phase angle being built into the frequency response (which represents voltage sensitivity over the full bandwidth): whether the phase angle is 0 degrees or 60 degrees, the voltage demanded from the amplifier remains the same. As a result you don’t have to worry that an amplifier is going to have to swing loads of extra voltage and current in order to cover the effects of a difficult phase angle.
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