Time domain

The term Time domain is commonly used to describe one of two "domains" of a waveform. Please see Amplitude domain for more details.

In digital audio recording and reproduction, the audio (voltage) waveform is "sampled" in a manner analogous to film consisting of a series of still photographs. Because it is necessary to sample audio at very high frequencies to accurately represent the highest (treble) frequencies present; the consistency of the timing of the conversion is paramount to good performance.

During reproduction, the timing of the DA conversion (or “de-sampling”) is equally important to accurate results. Any difference in the timing of the sampling or de-sampling will result in distortion of the waveform that causes it to differ from the original in both the time and amplitude domain. The way this distortion is perceived can be very different than the perception of harmonic or intermodulation distortions common to analog audio.

Relatively long-term variations in the sample frequency can result in the perceived pitch of the audio changing, while short-term variations such as jitter can result in the generation of non-musical distortions.