Flush-mounting in a wall boosts bass output of a loudspeaker not designed for it.

Evidence

The overall conclusion is that mounting this excellent little loudspeaker in a wall has left its overall performance substantially intact, but the bass output has been greatly increased, making it sound fat, thick and tubby. After all, it was not designed to be used in this manner. The solution in this case is to turn the bass down. Any competent equalizer can do it, or the old-fashioned bass control may just be optimum if the “hinge” frequency is around 500 Hz. — Toole, Floyd E, Sound reproduction- the acoustics and…, 1481

Categorization

• DEFINE: Defines the ‘hinge’ frequency concept — the frequency below which wall-mounting raises output, here around 500 Hz.