Frame array

This invention relates to acoustic "phased-array" antennas and their application to single and multi-beam directional loudspeakers and microphones, and more particularly to useful practical forms of said arrays when they have to be confined to the surrounding area of a display screen (such as in a TV or computer display). A method is shown of overcoming the major problems inherent in existing known array forms when disposed around a primarily rectangular screen. The transducers are provided in an irregular formation, such as a spiral formation or a squarised spiral formation.