Audio Op Amp DIP8 NJM2068D JRC U1 0.39 0.39 513-NJM2068D 1 NJM2068DD (quieter), NE5532AP (noisier), OPA2277PA (low power see docs) 2 Dual High Current Audio Op Amp DIP8 NJM4556AD JRC U3,U4 0.57 1.14 513-NJM4556AD 2 NJM4556ADD (TLE2062CP low power substitute see docs) 1 12 Volt Positive Fixed Regulator TO