Sound diagnostic system, sound diagnostic method, and non-transitory computer-readable recording medium

A sound diagnostic method comprising:

• calculating, from sound information on a sound produced by an apparatus, a sound pressure of each of a plurality of frequencies at each timing;
• calculating an autocorrelation function for a change, with time, of a representative value of the sound pressures of respective frequencies included in a target frequency band, among the plurality of frequencies;
• extracting one or more peak timings of the autocorrelation function;
• detecting a period of each of one or more abnormal sounds, based on the one or more peak timings;
• and
• identifying, based on the period, a causative component for each of the one or more abnormal sounds, among a plurality of components included in the apparatus.

A non-transitory computer-readable recording medium storing instructions that cause a computer to perform a sound diagnostic method, the sound diagnostic method comprising:

• calculating, from sound information on a sound produced by an apparatus, a sound pressure of each of a plurality of frequencies at each timing;
• calculating an autocorrelation function for a change, with time, of a representative value of the sound pressures of respective frequencies included in a target frequency band, among the plurality of frequencies;
• extracting one or more peak timings of the autocorrelation function;
• detecting a period of each of one or more abnormal sounds, based on the one or more peak timings;
• and
• identifying, based on the period, a causative component for each of the one or more abnormal sounds, among a plurality of components included in the apparatus.