If your matches have tested at fewer markers than you, you will want to encourage them to upgrade to see if the match holds up. You will be able to see the Most Distant Ancestor for your matches who have provided them. Look down the list to see if any look familiar.
In physics, sound is a vibration that propagates as a typically audible mechanical wave of pressure and displacement, through a medium such as air or water. In physiology and psychology, sound is the reception of such waves and their perception by the brain.
sound. 1. a pressure wave propagating through an elastic medium; waves with a frequency of 20â20,000 Hz cause the sensation of hearing. 2. the effect produced on the organ of hearing by vibrations of the air or other medium.