SRS iWow 3D
I've certainly heard of itand heard itand I agree it's pretty remarkable. Both the hardware dongle (seen here) and the software app use mathematical algorithms called head-related transfer functions (HRTFs) to model how we perceive sound coming from various directions to create a more immersive, "out of head" experience. The specific HTRF that's used depends on whether you are listening on headphones/earbuds, speakers, or in the car, which you select in the app, and the connected dongle is updated accordingly.
The iWow 3D also uses SRS's TruBass technology to enhance the low frequencies. This technology is based on a principle called "the missing fundamental." According to SRS, "A series of harmonics are emphasized in the range that a typical headphone can reproduce. The harmonics cause the ear/brain system to perceive bass about one octave lower than would normally be possible. The audio perception system fills in the "missing fundamental." TruBass also does dynamic processing to increase the impact of the bass and to limit driver excursion." Pretty darn cool if you ask me!
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