Editing Precedence effect (section)

===Ambience extraction===
The precedence effect can be employed to increase the perception of ambience during the playback of stereo recordings.<ref>{{cite journal |url=http://www.aes.org/e-lib/browse.cfm?elib=1481 |title=Extraction of Ambiance Information from Ordinary Recordings |last=Madsen |first=E. Roerbaek |journal=Journal of the Audio Engineering Society |date=October 1970 |pages=490–496 |volume=18 |number=5}}</ref> If two more speakers are placed to the left and right of the listener (in addition to the two main speakers), and are fed with the same program material but delayed by 10 to 20 milliseconds, the random-phase ambience components of the sound will become sufficiently decorrelated that they cannot be localized. This effectively extracts the recording's existing ambience, while leaving its foreground "direct" sounds still appearing to come from the front.<ref>{{cite journal|url=http://www.stereophile.com/content/extraction-ivsi-generation |title=Extraction vs Generation |journal=Stereophile |last=Katz |first=Bob |date=March 1988}}</ref><ref>{{cite book|title=Mastering Audio: The Art and the Science |last=Katz |first=Bob |year=2007 |pages=229–237 |publisher=Taylor & Francis |isbn=978-0240808376}}</ref>