I need a simple single supply amplifier that draws a lot of current when signal is applied. Without going into why, let's just say this is supposed to be part of a compressor. Distortion performance is not important. What is important is that it has a high ratio of current drawn in relation to the signal. So if the signal is low, the current drawn is low. If the signal is high, the current drawn is 100X as much.
So I have modeled and breadboarded the following circuit:
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This circuit works fine (with a 100pF cap across the PI outputs) but it doesn't draw nearly enough current. The transformer is a standard Radio Shack style output transformer (actually an Eagle LT700) with a 1K2 primary and 3R4 secondary.
Ultimately the problem is that I cannot pull more than 2mA through the power transistors. Can someone explain why?
My first guess is that the impedance relation between the phase inverter and power section stinks. But it's not crystal clear how to resolve that.
Ultimately I would like a current gain of 100:1. If I could make a 1W power amp out of this circuit, that would be ideal.