Just tested one side of my Zen -no joy ???

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I have just completed one side of the Aleph current source Zen. Hooked it up, rectifier fried and nearly took out my iron cored inductor (underspecified salvaged bit), replaced that. I have taken a friends advise and substituted basic TO3 power transistors to test the circuit. Transistors heat up nicely and test speaker has a soft hum when put up to the ear. I am using a tuner to generate the test signal (less than two volts). I can hear the signal very faintly. If I turn the amp off the hum disapears- to be expected- and the signal comes through slightly stronger.
I stripped down the circuit and rebuilt it to see if I had made a mistake, same result. there is slightly more than 0.66 voltage drop across R1, about 0.8, but there is 2 amps of current through it.
I will go back and look again in the morning. Any ideas as to what might be going wrong?
 
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