This original design is derived from the work of Dick Burwin, formally working at Analog Devices, later with Mark Levinson, in their hybrid group, in 1966. You can find this reference on Walt Jung's website in the historical section, somewhere.
I made a fet input and fet output version of this design in 1973 as the phono preamp stage of the Levinson JC-2. It is a GOOD, standard approach. Welcome to the real word of amplifier design, everyone.
