[Mrscbw]

Just had a quick question, maybe somebody can enlighten me. If this matrix M-stage is a pure class A amp, what is the purpose of the Class A Biasing mod?

 

[ETAHL]

 
Quote:

Just had a quick question, maybe somebody can enlighten me. If this matrix M-stage is a pure class A amp, what is the purpose of the Class A Biasing mod?

The drive transistors of the M-stage are configured in class A.
However, op-amps does not operate in class A. The switch of transistors inside op-amps are so fast that is far beyond the audio spectrum. Realistically, the Class A biasing mod is just modifying the sound signature of the op-amp, the biasing is so low with the mod that you get switching anyways. It should really be called class AB mod.

 

 

[Chris J]

To determine if the op amps truly are biased into Class A it really depends on how mich current gain the Matrix output stage has and therefore how how current the output stage draws.
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The transistors in the op amp output are only going to switch as fast as the input to the op amp, i.e. the audio signal into the op amp.