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 is a Pressure Wave. Sound is a mechanical wave that results from the back and forth vibration of the particles of the medium through which the sound wave is moving. If a sound wave is moving from left to right through air, then particles of air will be displaced both rightward and leftward as the energy of the sound wave passes through it.