Currently my pre-amp just has the Phono pre-amp and other line inputs (CD/Tape Deck) are just switched in the pre-amp without any amplification. I am planning to built a discrete op-amp buffer similar to the Marantz HDAM cicuit but with different components. I am mighty impressed by this circuit in the blue-ray player and think it can also benefit in the pre-amp. I shall built only 3 boards currently. Earlier i had built a class A pre-amp and also the DCB1 but was not impressed by them. I believe the DCB1 JFET was duplicate and hence did not benefit.