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Originally Posted by tw
These are the same people who recommend a plug-in UPS to 'clean' power, or spend $100 on Monster Cable wires because their gold connectors make better sound. Or will mark their speaker cables because those wires have polarity - one end connected to the speaker instead of the amp causes worse sound. I also smell the Wicked Witch of the West.
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Yup... I think my favorite, after the expensive power cords, is the directional cables. Pretty amazing stuff!!!
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Originally Posted by tw
The original amp was Class A. Class B intead amplifies one half of a sine wave. Class C only amplifies sine wave's peak. Class AB is two class B amps where one amplifies top half of a sine wave; other amplifies the bottom half.
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One quibble - Class A amplifiers are biased such that they are always on, which is why they are such pigs, and why they sound so good! They amplify the entire waveform.
Class B amplifiers are not biased so that they can only amplify one half (positive or negative) of a sine wave. They can be used as half a "push-pull" stage, or in lots of other applications.
Class AB amplifiers are biased so that they amplify just over half that sine wave, they are more efficient than Class A.
I believe (college was a LONG time ago) the thing you describe as Class AB is actually the push-pull topology. Two class B amplifiers biased so that each one can amplify one half of the sine wave. As you described, the trick is getting the point where one turns off and the other turns on to match exactly. If they don't you get rather nasty sounding cross-over distortion!
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Originally Posted by tw
Little useful is described in that white paper or article. A digital recording at 32Khz does not have all this distortion. Why then would a digital amplifier at 100 Khz have so much distortion? Well, the devil is in deatils not even implied in those articles. In theory, a Class D amp means perfect amplification - no distortion. And then we apply reality to the concept - those devilish details.
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Yeah, those details! What's the difference between theory and practice???
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Bill