The sweet spot is a term used by audiophiles and recording engineers to describe the focal point between two speakers, where an individual is fully capable of hearing the stereo audio mix the way it was intended to be heard by the mixer.
In the case of surround sound, this is the focal point between four or more speakers,[1][2] i.e., the location at which all wave fronts arrive simultaneously.
A discussion of methods and their benefits can be found in Merchel et al.[5] By means of such methods more than one listener can enjoy the sound experience as intended by the audio engineer, including the desired phantom source locations, spectral and spatial balance and degree of immersion.
Massive multi-channel audio systems that apply wave field synthesis or higher order ambisonics exhibit an extended optimal listening area instead of a sweet spot.
[6] Sound engineers also refer to the sweet spot of any noise-producing body that may be captured with a microphone.