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Okay the circuit i posted earlier got me thinking, can we have a class B idle current with a class A fidelity. This way no matter the output voltage, you'll always have one and the same efficiency number whereas class A amps tend to reduce their efficiency at lower output levels. Yeah sure why not? Here's how. You use a class A amp to drive a loadless load? How does that work you ask? We just cancel out the load impedance with a negative resistance feedback equal to the load resistance but opposite. How's the efficiency you ask? Well it depends. If you use only one speaker and make the other 4 Ohm load, a simple resistor, the efficiency will be low (31%). If you replace the resistor with a speaker, you'll effectively double the efficiency to 62% which is a typical value for class B amps, and you'll probably get more stability, because if one resistor is left and the speaker is reactive, the speaker impedance will vary and the resistor impedance will stay the same, thus throwing things off balance. When both resistors are the same speaker models they'll both be reactive and will change their impedance simultaneously, thus nullifying any off balance that could occur
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