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Old 11th January 2005, 08:00 PM   #1
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Default LM3875 and class A?

Has anyone tried this with the LM3875?
Is Class A always a better sound, better fidelity?
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Old 12th January 2005, 03:52 AM   #2
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LM3875 and class A ? Kidding ?
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Old 12th January 2005, 05:05 AM   #3
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I was'nt, it seems like you know, but don't say. I thought Class A was the best. Tell me more.
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Old 12th January 2005, 06:03 AM   #4
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there have been threads on this. see the thread about the "first watt gainclone".
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Old 12th January 2005, 06:10 AM   #5
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An amp works in class A if the bias current through the output device is so high that it never drops to zero with an ac signal.

The LM chips are internally biased in class AB mode and you have no access to it. However if the load is very low ( high impedance ) , possibly something over 1 K ohm , it might run class A. I am not quite sure if that would be true either because the biasing level is very low and probably not in a very linear region like normal class A.

In any case to interface a speaker to the chip and load it ( the chip) differently you will need external power transistors and they can be biased into class A .
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