Automatic volume limiter system
An automatic volume limiter system (AVLS) is an option that limits the maximum volume level and is enabled through software or hardware in stationary or portable media player devices used with headphones such as the Walkman or Sony PSP.{{cite web |url=http://www.gadgetcentral.com/wm-we01_intro.html |title=The Ultimate Collector's Item – Sony's 20th Anniversary Walkman |accessdate=2011-08-17 |publisher=GadgetCentral}} The aim of this feature is to stop the headphones drowning out all other noise, and to limit the noise from the headphones being heard by other people.{{cite web |url=http://www.us.playstation.com/Support/PSP/GettingStarted/s_psp_gs_SN.html#avls |archiveurl=https://web.archive.org/web/20080611120232/http://www.us.playstation.com/Support/PSP/GettingStarted/s_psp_gs_SN.html#avls |archivedate=2008-06-11 |title=Sony support page referring to the AVLS feature on the PSP}} It can also prevent listeners from damaging their hearing. This volume limit can be set by the manufacturer or customized by the user.