A loudspeaker system can have first and second loudspeakers selectively operable in a single-channel mode or in a multi-channel mode. In the single-channel mode, the first and the second loudspeakers are configured to simultaneously reproduce a substantially identical signal. In the multi-channel mode, the first loudspeaker reproduces a first-channel signal and the second loudspeaker reproduces a second-channel signal. The first-channel signal and the second-channel signal can constitute respective portions of a multi-channel signal. Such loudspeaker systems can also have a mode selector configured to select one of the single-channel mode and the multi-channel mode. In some embodiments, such selection can occur in response to one or more detected proximities of another loudspeaker system. Multi-zone loudspeaker systems are also disclosed.