mpc-host

mpc-host is a variable defined in `mpc.el'.
Its value is

"localhost"

Documentation:
Host (and port) where the Music Player Daemon is running. The
format is "HOST", "HOST:PORT", "PASSWORD@HOST" or
"PASSWORD@HOST:PORT" where PASSWORD defaults to no password, PORT
defaults to 6600 and HOST defaults to localhost.

You can customize this variable.