Zero-Crossing Recording Files

When the Song Meter Mini Bat 2's Recording format is set to include Zero-Crossing, these files are saved with the file extension .zc.

Zero-Crossing files are many times smaller than full-spectrum files of the same length, and they came into common use when recording and saving full-spectrum files with the high sample rates required for bat vocalizations was a much greater technical barrier. They are still used in applications where minimizing data storage use is a priority.

Zero-Crossing is a more limited format than full-spectrum .wav files. Zero-Crossing files can only record the single loudest frequency at any point in time, and no information about the loudness of a signal or any harmonic content is saved. When visualized on a time-frequency plot, Zero-Crossing files only appear as a series of dots tracing the loudest component at any given time.

Zero-Crossing File Metadata

Metadata is additional information embedded into each recording alongside the recorded audio. The Song Meter Mini Bat 2 saves metadata in the open GUANO format. Software that supports the GUANO format can view these metadata fields. Kaleidoscope Pro Sound Analysis Software can display these fields with or without a paid license. See GUANO Metadata Fields for a list of metadata fields included in this format.

Unlike full-spectrum .wav files, Zero-Crossing file metadata does not contain a record of the Song Meter Mini Bat 2's settings.