At your risk. protect your ears from high SPL.
A 10K load resistor was added at the 3rd stage which is a K170 JFET. The output transformer used is about 10 to 1. Quiescent current is 1mA at Vb=24V, Vd=14V. It sounds nice and loud driving the Sennheiser HD580 in mono i.e. (150ohms).
A source resistor bypass capacitor of 100uF was added to the 1st K177 stage otherwise overall gain is too low (an input transformer has not been tried yet on this preamplifier).
The potentiometer separating 2nd and 3rd stage is at the time being 470K log.
The preamp driven at the time being by a Lipshitz RIAA inverse network sounds very nice (one channel tested only in mono).
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