A hearing aid of the present invention is convenient to repair and replace. The hearing aid includes: (i) an out-of-canal assembly comprising a power source (e.g., a battery) and a processor, and (ii) an in-canal assembly comprising a microphone and a receiver. The out-of-canal assembly is selectively, removably, electrically coupled to the in-canal assembly. Sound perceived by the in-canal assembly is processed by the out-of-canal assembly and transmitted to the user's eardrum. The in-canal assembly is conveniently, selectively decoupled from the out-of-canal assembly for convenient replacement or repair.