Playing with regulators
Just an update on my beta boards and regulators used. For my Raspberry Pi HAT DAC I am currently running two of these XLCLN Regulator boards. One with a TPS7A4701 (4uV output noise) regulator for powering the DAC, and the other with a linear LT1085CT-5 regulator for powering the Raspberry Pi. Still absolutely dead quiet and I am very very happy with the setup now. Just be aware that the LT1085CT-5 pinout is different to the board layout.
I was running a MC7805CTG 5V (10uV output noise) regulator previously for the Raspberry Pi, but started picking up problems with the Pi not booting or communicating (WiFi or UTP) properly – so this regulator does not seem to give enough current for running a Pi. The LT1085 3A now works very well. Probably not the quietest regulator out there, but I cannot hear a difference in my setup.