An example implementation may involve a control device detecting a trigger condition that initiates calibration of a plurality of playback devices. The control device may send, to the playback devices of the plurality, respective commands that instruct the playback devices to repeatedly emit the calibration sound according to a sequence. The commands may instruct the one or more playback devices to stagger emission of the calibration sounds such that each emitted calibration sound is delayed relative to a preceding calibration sound in the sequence. The control device may detect the emitted calibration sounds via a microphone.