A power supply only has a “sound” if you are hearing hum. A phono preamp needs only a tiny amount of power to function and any power source with reasonable filtering will be fine. If you want to be a purist, set up your phono preamp to be powered by batteries.

it’s not the tube amp, it’s the high efficiency speaker. With these speakers noise will be higher just like everything else. There’s nothing inherently noisier about a tube amplifier.