The MUSIC algorithm (multiple signal classification) is a well-known high-resolution method to sound source localization. However, as it is essentially narrowband, several extensions can be envisaged when dealing with broadband sources like human voice. This paper presents such extensions and proposes a comparative study w.r.t. specific robotics constraints. An online beamspace MUSIC method, together with a recently developed beamforming scheme, are shown to constitute a mathematically sound and potentially efficient solution.