Q-Sound

Background

Q-Sound is the original name for a positional three-dimensional (3D) sound processing algorithm from Q-Sound Labs that creates 3D audio effects from multiple monophonic sources and sums the outputs to two channels for presentation over regular stereo speakers. Q-Sound was eventually re-dubbed "Q1" after the introduction of "Q2," a positional 3D algorithm for headphones. As the company's spatial audio algorithm family grew, and multi-speaker surround system support was added to the positional 3D process, the Q-Sound positional 3D audio process became known simply as "Q3D". Q-Sound was used in most arcade games running on Capcom's CPS-2 arcade system such as Super Street Fighter II, Darkstalkers, Marvel vs. Capcom, Eco Fighters, Cyberbots, Super Muscle Bomber, and it was also used on the Sony ZN-1 and ZN-2 for the Street Fighter EX series, Rival Schools, Star Gladiator, and until Sonic Adventure for the Sega Dreamcast.

Logo (September 10, 1993-December 22, 2003, January 19, 2006)

Visuals: Basically a black screen with the Q-Sound logo in the middle and the blue words Virtual Audio surround the middle. The byline, copyrights, and how the Virtual Audio System works go on the bottom along with a Capcom logo on the very bottom. Usually at the end of the theme it takes you to a ''Winners Don't Use Drugs" Screen, more copyrights, another Capcom logo, or it just stays there until a demonstration of the game begins.

Variant: A widescreen version exists on Capcom Classics Collection Reloaded for the PSP. Some games, like Marvel Super Heroes and the aforementioned Capcom Classics Collection Reloaded remove the Capcom logo.

Technique: A still, sprite-based graphic.

Audio: Either of those 4 themes would play, changing their style on each game:

First Theme: A jazzy 12-note bell (or piano) theme with a bass guitar, ending with some chimes.
Second Theme: A 5-note theme, with 6 more notes after the last note hits.
Third Theme: An 11-note synth theme.
Fourth Theme: Two slow ascending piano arpeggios.

Other games may have the logo silent.

Theme Variants: Below there are some notable variants of the themes (mainly the first one):

Sometimes, the last note of the first theme is extended, making the chimes inaudible. This was spotted on some Marvel and Street Fighter games.
On Super Street Fighter II, Super Street Fighter II Turbo, Eco Fighters, and Hyper Street Fighter II, The first theme is high-pitched.
On Super Puzzle Fighter II Turbo, the first theme is played on a marimba.
On the Vampire/Vampire Hunter series and a few other games the chimes are played throughout the whole theme.
On Star Gladiator 2, the second theme is played on a piano that echoes.
On Street Fighter EX, the first theme is played on high synthesizers.

Availability: Available on every CPS-2 supported game you can find (except for Mighty! Pang and Puzz Loop 2, in which both do not have these). The version with the first theme can be found on most Street Fighter and Marvel games as well as Mega Man: The Power Battle and it's sequel, Mega Man 2: The Power Fighters. The second theme is seen in Japanese CPS1/2 games although it can be found on Street Fighter Alpha 3 and the Capcom Classics Collection Reloaded variant. The third theme is available on Arika games, including Street Fighter EX2 and Tetris: The Grand Master. The fourth theme has been only spotted on Dimahoo so far. It officially last appeared on Hyper Street Fighter II. It later appeared on re-releases of Capcom arcade collection games (Mainly Capcom Classics Collection and Street Fighter Alpha Anthology, which emulates the arcade versions) and Street Fighter Alpha 3 MAX for the PSP. The logo is removed on modern releases of CPS-2 games. However, it can still be seen on Street Fighter Alpha 3 on the Street Fighter 30th Anniversary Collection, the jingle itself can be heard on all of the games' soundtracks in the Music section in the Museum. The jingle also appears on Capcom Fighting Collection, playing over the standard Capcom logo.