I assume that you want 50VDC? How much current needs to be supplied? Does the voltage need to be regulated? Will the current demand be constant or will it vary? What about sonics? Poor choices made in designing a PS can destroy the sonics of the gear it's used in. Without more information no one is going to be able to help you. Besides voltage and current requirements and the possible need for regulation there are issues such as: noise (how much ripple will the following circuits tolerate), transformer ringing, switching noise generated by silicon rectifiers, etc. Also, many if not most audio circuits, analog output stages in particular, include the PS in the AC signal current loop (a capacitor acts like a short to an AC signal). The filter cap in the PS will most often be in the signal path and affect the sound of an amp. It would help if you'd indicate what type of equipment this PS is going into.