No only need one supply that's got enough Amps. Regards the Amps then rule of thumb is you only need 68% of total number of motor Amps IE: 3x 4.1A motors=12.3/68%= 8.4A

So 60V 8.5A PSU will be fine for 3 x motors. Max Voltage of the PSU should be roughly 10% less than drives Max voltage never run same voltage has drives else you run big risk of damage to drives.

Often with larger supplies finding just the right size is difficult often meaning some compromise on volts. Volts make big difference to stepper speeds so if it's big enough compromise then it can be less than ideal. So often it's easier and usually cheaper to build your own toroidal supply to give your exact requirements.
Unregulated Toroidal supply is also more suited to CNC/stepper motors anyway has they handle back EMF better.

Look around the forum and you'll see many examples of people building them, they are very easy to build.