This is similar to the JHL design that i commented on see that post from a few weeks ago. But i will add Why Why Do people Still insist on single end input stages and coupling caps man this is not the 60's. Also using the output transistors with the Collectors connected to the Load results in an extreamly large output Impedance that must use large Amounts of Feedback to lower it and Then through a low impedance Load on the Output and the output stage will totaly lose it.
Thanks for pointing us to this, Although i think great designs for headphone amp of all Kinds are from headwize/ Head-Fi members.
DISCLAIMER: This is only my View if any one has objections refer to my past posts i have not the time to respond again to the same thing.