Digital mixer

摘要

A digital mixer (100) comprises a storage (102) that previously stores a user key (310) of a guest including authority data specifying an authority of the guest as a default user; another storage (110) that stores a user key (310) for a user other than the guest; and a control portion capable of automatically logging into the digital mixer (100) with the user key (310) of the guest when power of the digital mixer (100) is turned on. The control portion allowes a user other than the guest to log into the digital mixer (100) after checking a user password. The control portion is capable of automatically logging into the digital mixer (100) with the user key (310) of the guest when a current user other than the guest logs out from the digital mixer (100). The digital mixer (100) further comprises a setting portion that sets and changes the authority of the guest based on an instruction of a specific user who has a specific authority to set and change the authority of the guest.