{"id":3180,"date":"2014-01-11T21:38:37","date_gmt":"2014-01-11T21:38:37","guid":{"rendered":"http:\/\/really.zonky.org\/?p=3180"},"modified":"2014-01-11T23:19:15","modified_gmt":"2014-01-11T23:19:15","slug":"down-mixing-quadrophic-and-5-1-surround-sound-with-sox","status":"publish","type":"post","link":"https:\/\/really.zonky.org\/?p=3180","title":{"rendered":"Down Mixing Quadrophic and 5.1 Surround Sound with SOX"},"content":{"rendered":"<p>As categorised, this is a &#8220;working note&#8221; and explains how I &#8216;down mix&#8217; quadrophic FLAC files into stereo files with the assistance of\u00a0<em>sox<\/em>. This may well not be the best method and indeed I may be getting it totally wrong &#8211; who knows what two channels are supposed to go where?<\/p>\n<p>It turns out that my portable media player doesn&#8217;t understand FLAC files with more than two channels, and as I have a number of these obtained from somewhere I needed a way to make them playable. The first step is to identify FLAC files with more than two channels. It turns out that the venerable <em>file<\/em> does that quite adequately :-<\/p>\n<pre>\r\n% file one.flac two.flac\r\none.flac:              FLAC audio bitstream data, 24 bit, stereo, 96 kHz, 24179840 samples\r\ntwo.flac:              FLAC audio bitstream data, 24 bit, 4 channels, 96 kHz, 24179840 samples\r\n<\/pre>\n<p>As you can see the third column of the information about the file identifies the number of channels; it also identifies 5.1 surround sound files as 6 channel files. And quite possibly wilder and woollier kinds of channel numbers too.<\/p>\n<p>Now onto the conversion. This is simply the following :-<\/p>\n<pre>\r\n% sox input-file.flac output-file.flac remix 1v0.5,3v0.5 2v0.5,3v0.5 norm\r\n% file output-file.flac\r\noutput-file.flac:      FLAC audio bitstream data, 24 bit, stereo, 96 kHz, 24179840 samples\r\n<\/pre>\n<p>The details of what sox command to use \u2026 and specifically the remix parameters came from a post discussing the problem <a href=\"http:\/\/forum.doom9.org\/archive\/index.php\/t-152034.html\">here<\/a>. I&#8217;m not qualified to assess the details, but the results <em>seem<\/em> fine. For extra points, the remix parameters for 5.1 surround sound are: <em> 1v0.3694,3v0.2612,4v0.3694 2v0.3694,3v0.2612,5v0.3694<\/em>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>As categorised, this is a &#8220;working note&#8221; and explains how I &#8216;down mix&#8217; quadrophic FLAC files into stereo files with the assistance of\u00a0sox. This may well not be the best method and indeed I may be getting it totally wrong &#8211; who knows what two channels are supposed to go where? It turns out that <a href='https:\/\/really.zonky.org\/?p=3180' class='excerpt-more'>[&#8230;]<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"_share_on_mastodon":"0"},"categories":[4,226],"tags":[],"class_list":["post-3180","post","type-post","status-publish","format-standard","hentry","category-it","category-working-notes","category-4-id","category-226-id","post-seq-1","post-parity-odd","meta-position-corners","fix"],"share_on_mastodon":{"url":"","error":""},"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p1f2KI-Pi","_links":{"self":[{"href":"https:\/\/really.zonky.org\/index.php?rest_route=\/wp\/v2\/posts\/3180","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/really.zonky.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/really.zonky.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/really.zonky.org\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/really.zonky.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3180"}],"version-history":[{"count":2,"href":"https:\/\/really.zonky.org\/index.php?rest_route=\/wp\/v2\/posts\/3180\/revisions"}],"predecessor-version":[{"id":3184,"href":"https:\/\/really.zonky.org\/index.php?rest_route=\/wp\/v2\/posts\/3180\/revisions\/3184"}],"wp:attachment":[{"href":"https:\/\/really.zonky.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3180"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/really.zonky.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3180"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/really.zonky.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3180"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}