An exemplary sound processor apparatus included in an auditory prosthesis system includes a linear regulator and a sound processing integrated circuit (“IC”). The linear regulator 1) receives a source voltage signal having a source voltage level and provided by an external power source, 2) drops the source voltage level to an intermediate voltage level, and 3) outputs an intermediate voltage signal having the intermediate voltage level. The sound processing IC 1) performs one or more sound processing operations with respect to an audio signal presented to a patient associated with the auditory prosthesis system, 2) receives the intermediate voltage signal having the intermediate voltage level, 3) converts the intermediate voltage level into one or more supply voltage levels, and 4) outputs one or more supply voltage signals having the one or more supply voltage levels.