Journal Article
Distribution of the Phonograph Signal Rate of Change
Journal of the Audio Engineering Society · Volume 28 · Issue 5 · pp. 316–319 · May 1980
Abstract
The distribution of the rate of change of the RIAA-corrected phonograph signal was measured. Thirteen recordings representing various kinds of music were used, including both processed and directly cut disks. The measurement was designed to give for each music sample the total time during which the signal rate of change exceeds a certain threshold value. The total times as a function of threshold are presented in the range of 10 µs to 1 s for music samples with a length of about 3 min each. Also, the peak voltages of the signal and the signal derivative were measured. The distribution of the signal rate of change is dependent on the music character giving the high content of large rate of change values for pop and brass music, and lower values for certain classical and purely vocal music samples. The maximum rate of change varies from 5 to 110 V/ms and the maximum peak-to-peak voltage from 1 to 7 V in the output of the RIAA amplifier. The normalized value, that is, the maximum rate of change divided by the maximum peak-to-peak voltage, ranges from 3 to 25 V/V/ms.
