  A method for analyzing sampling jitter in audio equipment is proposed. The
method is based on the time-domain analysis where the time fluctuations of
zero-crossing points in recorded sinusoidal waves are employed to characterize
jitter. This method enables the separate evaluation of jitter in an audio
player from those in audio recorders when the same playback signal is
simultaneously fed into two audio recorders. Experiments are conducted using
commercially available portable devices with a maximum sampling rate of 192~000
samples per second. The results show jitter values of a few tens of picoseconds
can be identified in an audio player. Moreover, the proposed method enables the
separation of jitter from phase-independent noise utilizing the left and right
channels of the audio equipment. As such, this method is applicable for
performance evaluation of audio equipment, signal generators, and clock
sources.
