But swimmers can't perform flamingos and cranes in unison if the music is only audible above the water. So, Oceanears technology provides a method for getting the sound out without breaking the bank. Most air based audio speakers rely on a moving coil design that requires a large displacement of air molecules to create noise. According to Harper, moving water that long distance causes problems. Instead, Oceanears speakers rely on piezoelectric technology similar to smaller, above-water tweeters. Voltage applied to ceramic causes much smaller vibrations that are nearly invisible to the naked eye. With water molecules much more tightly packed than those in air, the small displacements can put out much bigger sounds under the water than on ground.