QSound
QSound is the original name for a positional three-dimensional (3D) sound processing algorithm from QSound Labs that creates 3D audio effects from multiple monophonic sources and sums the outputs to two channels for presentation over regular stereo speakers. QSound was eventually re-dubbed "Q1" after the introduction of "Q2", a positional 3D algorithm for headphones. Later multi-speaker surround system support was added to the positional 3D process, the QSound positional 3D audio process became known simply as "Q3D". QSound was founded by Larry Ryckman (CEO), Danny Lowe and John Lees. Jimmy Iovine served as SVP of Music  and Shelly Yakus as VP of Audio Engineering in its formative years. Technology. QSound is essentially a filtering algorithm. It manipulates timing, amplitude, and frequency response to produce a binaural image. Systems like QSound rely on the fact that a sound arriving from one side of the listener will reach one ear before the other and that when it reaches the furthest ear, it is lower in amplitude and spectrally altered due to obstruction by the head. However, the ideal algorithm was arrived at empirically, with parameters adjusted according to the outcomes of many listening tests. 3D positional processing like  QSound, the multi-channel QSystem professional processor used in the production of pop music and film audio, is distinct from stereo expansion like QSound QXpander or SRS(R) Sound Retrieval System. Positional 3D audio processing is a producer-side technology. It is applied to individual instruments or sound effects, and is therefore only usable at the mixing phase of music and soundtrack production, or under realtime control of game audio mixing software. Stereo expansion (processing of recorded channels and background ambience) is primarily a playback process that can be arbitrarily applied to stereo content in the end-user environment using analog  integrated circuits or digital signal processing (DSP) routines. Adoption. The system was used in all Capcom CP System Dash, CP System II titles as well as several console games and the Sony ZN-1 and ZN-2 hardware arcade games such as "Battle Arena Toshinden 2". QSound was utilized on Sting's 1991 album, "The Soul Cages", Roger Waters's 1992 album "Amused To Death", Luther Vandross's 1991 album, "Power of Love", Madonna's 1990 album, "The Immaculate Collection", and Paula Abdul's 1991 album, "Spellbound". Electronic Arts, Activision, Microsoft Game Studios, Sega, Virgin Interactive, TDK Mediactive, Bullfrog Productions, and Lionhead  Studios have also used the technology, mostly through the use of the QMixer software development kit to implement audio positioning, mixing and control directly in the game software. Later versions of QMixer added support for 3D-accelerated hardware through the low-level Microsoft DirectSound3D Application Programming Interface. Q3D has been incorporated in a variety of computer sound cards and sound card drivers. While the system is known by some for its use in video game titles, the first QSound chip used for that purpose was not created until 1991, while QSound had been developed in the late 1980s and has  been used in everything from screensavers to television programming. Some TVs were also produced with this technology. Several 1990s music albums were also "mixed in QSound" (see below) using the QSystem or QSystem II hardware processors, and many other music releases have been enhanced with QSound effects using software plug-in versions of the QSystem and other software utilities. (The QSound website maintains a list of known projects.) In 2003, Q3D was added to the list of components in QSound Labs' microQ, a small-footprint, performance-optimized software digital audio engine aimed at the mobile market (i.e. cellphones and the  like). Q3D enables 3D sound for handheld gaming and can be controlled in Java games via the JSR-234 application programming interface. Awards. QSound won "Electronic Entertainment"s 1993 "Most Promising" award; the editors called it the "hottest new audio technology around". Selected games using QSound. Notable games include: Selected albums "mixed in QSound". Over 60 albums feature QSound processing. Some notable examples include: