Sound Retrieval System

The Sound Retrieval System (SRS) is a patented psychoacoustic 3D audio processing technology originally invented by Arnold Klayman in the early 1980s. (The original SRS patents are US 4866774 , US 4748669  and US 4841572 , which expired between 2006 and 2008. Patents may apply in other countries). The SRS technology applies head-related transfer functions (HRTFs) to create an immersive 3D soundfield using only two speakers, widening the "sweet spot," creating a more spacious sense of ambience, and producing strong localization cues for discrete instruments within an audio mix. SRS is not a Dolby matrix surround decoder but works with normal stereo recordings.

Initially Hughes Aircraft, for whom Klayman was doing acoustic consulting at the time, offered a standalone SRS audio processor, as well as licensing the technology to Sony and Thomson (RCA) for inclusion in their products. In the early 1990s, Hughes sold off its non-aerospace-related holdings, and a group of entrepreneurs formed SRS Labs to acquire the SRS technology.

Many TV sets employ built-in SRS to make their built-in audio systems sound "bigger." An article in the November 1994 issue of Consumers Digest magazine tested several SRS-equipped sets from Sony and other manufacturers and concluded that the circuit was essentially a gimmick in these products due to their small, close-set speakers and low-wattage amplifiers. SRS is not a panacea for audio systems that are marginal to begin with; it works best with full-range, high-fidelity sound reproduction.

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