| A speaker radiates compression
waves from the front and back that are out of phase. When the
speaker is small compared to the wavelength, the front and back
waves diffract to almost perfect circles as they leave the speaker.
The two waves interfere and very little sound is produced. Mounting
the speaker in the center of a large baffle board, separates
the front and back waves and removes the interference. Because
baffle boards must be large, a better alternative in a private
house is a wall-mounted speaker, with the front in the bedroom
and the back in the lounge. |
