Description and classification of the sounds usually involves auscultation of the inspiratory and expiratory phases of the breath cycle, noting both the pitch (typically described as low, medium or high) and intensity (soft, medium, loud or very loud) of the sounds heard.
"Rhonchi" and "rales" are obsolete terminology whose use in the literature has been variable. The terms wheeze and crepitation have replaced them.
Vesicular - heard over most of the lungs. Often described as similar to a soft rustle (of leaves). The inspiratory sounds are faster and louder and longer than expiratory sounds. The expiratory intensity is soft and the pitch is low die away after the first third of the expiratory phase.
Bronchovesicular - heard over the 1st and 2nd intercostal spaces and the interscapular area. The inspiratory and expiratory phases are roughly equal in length.
Bronchial - may be normally heard over the manubrium. Expiratory phase is greater than inspiratory. The expiratory pitch is high and intensity is loud.
Tracheal - heard directly over the trachea. Inspiratory phase equals the expiratory phase. The sound is very loud and the pitch very high.