Wisdom Audio Wisdom Series LS4

The LS4 is the top of Wisdom's namesake Wisdom Series and the fullest expression of what the company does. A single 80-inch planar magnetic line source covers eight octaves, and one LS4 will produce in excess of 130 dB at twelve feet — output figures that belong to horn-loaded professional cinema systems rather than to anything that can disappear into a wall.

The reason to use a line source at that height is behavioural rather than statistical. A tall column radiates uniformly across the width of a room and largely eliminates floor and ceiling reflections, so timbre stays consistent from seat to seat and level falls off far more slowly with distance than it does from a point source. In a room with three rows, that is the difference between one good seat and nine.

It is offered free-standing as the LS4, on-wall as the LS4m and in-wall as the LS4i, with the in-wall version stackable and intended to sit behind an acoustically transparent screen. The diaphragm is a lightweight PEEK film, and custom colours are available. Which configuration a room takes is an architectural decision as much as an acoustic one.