Rc 121k
Rd 464k
C1 4.7uF - 5.1uF
C2 0.1uF - 0.12uF
Improvements to the RA-1?
Caps sizes.
Other Opams: Original JRC4556 - JRC2114D - AD826 (no work fine) - OPA2604
JRC4556 - Mylar caps 0,1uF (but with Auricaps is so warn - not work fine for me)) - Auricaps 4,7uF