In the time domain, as Hugh Le Caine used to say, everything is amplitude (displacement). As I understand this, frequency and phase are derived from amplitude in [quantized] time.
On 2010, Dec 29, at 2:47 AM, ita katz wrote:
But the amplitude does not carry all the information needed to recreate the sound. Similarly, the "Sound-on-Film" entry states:
(SVA) recording, encoding a two-channel audio signal as a pair of lines
running parallel with the film's direction of travel through the
projector. The lines change area (grow broader or narrower) depending on
the magnitude of the signal.
Again, what encodes the frequency/phase?