{"id":154,"date":"2013-01-15T13:41:08","date_gmt":"2013-01-15T18:41:08","guid":{"rendered":"http:\/\/bookofsand.net\/voltage\/?p=154"},"modified":"2013-01-22T23:53:57","modified_gmt":"2013-01-23T04:53:57","slug":"guided-by-a-signal-in-the-heavens","status":"publish","type":"post","link":"http:\/\/bookofsand.net\/voltage\/?p=154","title":{"rendered":"GUIDED BY A SIGNAL IN THE HEAVENS"},"content":{"rendered":"<p>The nation that brought us the <a href=\"http:\/\/www.soundonsound.com\/sos\/apr08\/articles\/radiophonic.htm\" target=\"_blank\">BBC Radiophonic Workshop<\/a> has now engineered another advance in electronic sound processing. It seems forensic experts on London&#8217;s police force have been <a href=\"http:\/\/www.bbc.co.uk\/news\/science-environment-20629671\" target=\"_blank\">recording the ever-fluctuating hum of the national power grid<\/a> for the past seven years. <\/p>\n<p>Why?  Because almost any audio recorded in the UK during that time will have the same hum embedded in it&#8230; so the cops can use their reference track to find out precisely when recordings entered into evidence were made &#8212; and whether they&#8217;ve been edited:<\/p>\n<blockquote><p>Any digital recording made anywhere near an electrical power source, be it plug socket, light or pylon, will pick up this noise and it will be embedded throughout the audio. &#8230;<\/p>\n<p>Comparing the unique pattern of the frequencies on an audio recording with a database that has been logging these changes for 24 hours a day, 365 days a year provides a digital watermark: a date and time stamp on the recording. &#8230;<\/p>\n<p>&#8220;Even if [the hum] is picked up at a very low level that you cannot hear, we can extract this information.&#8221;<\/p><\/blockquote>\n<p>That&#8217;s right: the UK now has nationwide audio timecode.<\/p>\n<p>(Via <a href=\"http:\/\/new-aesthetic.tumblr.com\/day\/2012\/12\/13\/\" target=\"_blank\">The New Aesthetic<\/a>)<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The nation that brought us the BBC Radiophonic Workshop has now engineered another advance in electronic sound processing. It seems forensic experts on London&#8217;s police force have been recording the ever-fluctuating hum of the national power grid for the past seven years. Why? Because almost any audio recorded in the UK during that time will [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[7],"tags":[],"_links":{"self":[{"href":"http:\/\/bookofsand.net\/voltage\/index.php?rest_route=\/wp\/v2\/posts\/154"}],"collection":[{"href":"http:\/\/bookofsand.net\/voltage\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/bookofsand.net\/voltage\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/bookofsand.net\/voltage\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/bookofsand.net\/voltage\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=154"}],"version-history":[{"count":0,"href":"http:\/\/bookofsand.net\/voltage\/index.php?rest_route=\/wp\/v2\/posts\/154\/revisions"}],"wp:attachment":[{"href":"http:\/\/bookofsand.net\/voltage\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=154"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/bookofsand.net\/voltage\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=154"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/bookofsand.net\/voltage\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=154"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}