A lot of stepper drivers have a 50v max so that is probably why 48v is so common. Yo will get more speed at the higher voltage. Generally unregulated power supplies are better for steppers. See refence below. This is similar to the one I am using. https://www.automationtechnologiesin...gulated-230vac It is 50 volt 10amps.
Reference: https://www.teknic.com/selecting-power-supply/