A method and system for encoding data in audio are provided. A sequence of time deltas is generated at least partially based on a set of data. At least some of the time deltas are less than a threshold at which a human naturally detects an echo. A second audio channel is generated from a first audio channel, the second audio channel being temporally shifted relative to the first audio channel using the sequence of time deltas. The first and second audio channels are played back simultaneously via at least one audio transducer. The composite audio channel is registered via at least one microphone and processed to identify the first and second audio channels that are at least partially relatively temporally shifted. A sequence of time deltas by which the second audio channel is shifted temporally relative to the first audio channel is determined, and a set of data is decoded at least partially therefrom.