It was a loop-based music sequencer, in which Acid Loop files could be simply drag-and-dropped then automatically adjust to the tempo and key of a song with virtually no sonic degradation.

The software became very popular in the late 1990s and early 2000s among composers, producers, and DJs interested in quickly creating beats, music textures, or complete compositions and orchestrations, that would work with virtually any tempo or key signature.

[2] Sonic Foundry sold its Acid, Vegas, Sound Forge, CD Architect, Siren, VideoFactory, ScreenBlast, and Batch Converter product lines to Sony Pictures Digital in July 2003; the merger resulted in the new Sony Creative Software division.

The update came with new modern features including an enhanced interface, support for 64-bit, additional samples, VST3 support, over 20 DirectX audio effects, the ability to mix in 5.1 surround sound, and new features named Media Manager, BeatMapper, and Chopper.

An Acidized loop is a specially prepared WAV audio file, which can be created using an audio-editing tool such as Sound Forge.