Gobo is a slang term used by sound recording engineers to refer to a movable acoustic isolation panel.

A luthier (/ˈluːtiər/ LOO-ti-ər)[1] is someone who builds or repairs string instruments generally consisting of a neck and a sound box. The word "luthier" comes from the French word luth, which means lute. A luthier was originally a maker of lutes, but the term now includes makers of stringed instruments such as the violin or classical guitar.

Loudness - Subjective impression of the intensity of a sound.

Longitudinal wave - A wave in which vibrations are in the direction of propagation of sound as are sound Wavesin air.

Live - A reverberant acoustical condition, usually used in reference to a room whose many reflective surfaces encourage a lengthy reverberation time.

LEDE - Live end, dead end. An optimal acoustical treatment plan for rooms in which one end is highly absorbent and the other end reflective and diffusive.

Leakage - Any unwanted sound picked up by (or “leaking” into) a microphone from another instrument or loudspeaker. Sound from one room that is heard in another.

Law of the first wavefront - The first wavefront falling on the ear determines the perceived direction of the sound.

Late reflection - Reflected energy that occurs a greater distance away from the source than an early reflection. Sometimes referred to as “slap-back” or echo.

Kilohertz / kHz - 1,000 Hz increments. See Hertz.