Apogee supports the connection of ONE to the USB hub in Apple Cinema Displays. Otherwise, it is recommended to connect ONE directly to a USB port on your Mac.
You can connect ONE to powered studio monitors with an 1/8” TRS to dual 1/4” TS Y cable. The 1/8” end will connect to ONE’s headphone output and each 1/4” end will connect to each monitor, left and right.
Any Apogee product that includes microphone inputs with 48v phantom power is designed to handle loads up to a complete short, or 14.1 mA. This will properly power any microphone.