We attempted to identify the sound source of snoring only by analyzing snoring sounds. Snoring sounds were tape-recorded at home and brought to the hospital by the patients, and with a sound spectrograph and a signal processor we analyzed the results and compared them with those of patients whose sources of snoring were confirmed fiberscopically.
1. Patients whose fundamental frequency (FF) was fairly regular, the FFs ranged from 15 Hz to 300Hz, usually under 170Hz.
2. In some cases, the FF changed in a single snore. A decrease of FF was observed more often than a increase.
3. The pitch perturbation quotients of ordinary snoring sounds were larger than those of vocal fold vibrations.
4. Among the sound sources confirmed fiberscopically, the great majority were vibrations of the soft palate, the FFs ranging from 20 Hz to 200 Hz. The few other sound sources of snoring comfirmed were: vocal folds (210 to 300Hz), the arytenoids (130 to 340Hz), the epiglottis (45 to 90Hz), and the tongue base (40 to 50HZ).
