{"id":7663,"date":"2021-06-05T12:06:00","date_gmt":"2021-06-05T10:06:00","guid":{"rendered":"https:\/\/www.loudspeakers.audio\/?post_type=ufaq&#038;p=7663"},"modified":"2022-11-05T23:41:54","modified_gmt":"2022-11-05T21:41:54","slug":"clock-mismatch-between-player-and-recorder","status":"publish","type":"ufaq","link":"https:\/\/www.loudspeakers.audio\/fr\/faqs\/clock-mismatch-between-player-and-recorder\/","title":{"rendered":"Ecart de vitesse entre lecture et enregistrement"},"content":{"rendered":"<style>.ewd-ufaq-post-margin-symbol { color: #4055a9 !important; }.ewd-ufaq-post-margin-symbol { border-color: #53037d !important; }.ewd-ufaq-faq-display-style-block.ewd-ufaq-post-active, .ewd-ufaq-faq-display-style-block.ewd-ufaq-post-active a,.ewd-ufaq-faq-display-style-block:hover, .ewd-ufaq-faq-display-style-block:hover a, .ewd-ufaq-faq-display-style-block:hover h5 { background-color: #617ffe !important; }.ewd-ufaq-faq-display-style-border_block.ewd-ufaq-post-active, .ewd-ufaq-faq-display-style-border_block:hover, .ewd-ufaq-faq-display-style-border_block:hover h5 { background-color: #617ffe !important; }.ewd-ufaq-faq-display-style-border_block .ewd-ufaq-faq-body { border-color: #617ffe !important; }.ewd-ufaq-faq-display-style-border_block .comment-reply-title, .ewd-ufaq-faq-display-style-border_block:hover .comment-reply-title { background-color: transparent !important; }.ewd-ufaq-faq-display-style-block:hover .ewd-ufaq-post-margin-symbol, .ewd-ufaq-category-post-margin-symbol, .ewd-ufaq-faq-display-style-block:hover h5 { color: #4055a9 !important; }.ewd-ufaq-faq-display-style-border_block:hover .ewd-ufaq-post-margin-symbol, .ewd-ufaq-category-post-margin-symbol, .ewd-ufaq-faq-display-style-border_block:hover h5 { color: #4055a9 !important; }.ewd-ufaq-faq-header-title a { color: #7b2c2c !important; }div.ewd-ufaq-faq-title h5 { color: #4055a9 !important; }div.ewd-ufaq-faq-post p { color: #000000 !important; }div.ewd-ufaq-faq-category-title h3 { color: #2b1010 !important; }div.ewd-ufaq-faq-categories, div.ewd-ufaq-faq-tags { color: #9b4c4c !important; }div.ewd-ufaq-faq-categories, div.ewd-ufaq-faq-tags { margin: 30 !important; }<\/style><div  class=\"ewd-ufaq-faq-list ewd-ufaq-page-type-infinite_scroll ewd-ufaq-category-tabs-\" id='ewd-ufaq-faq-list'>\n\n\t<input type='hidden' name='show_on_load' value='' id='ewd-ufaq-show-on-load' \/>\n<input type='hidden' name='include_category' value='' id='ewd-ufaq-include-category' \/>\n<input type='hidden' name='exclude_category' value='' id='ewd-ufaq-exclude-category' \/>\n<input type='hidden' name='orderby' value='set_order' id='ewd-ufaq-orderby' \/>\n<input type='hidden' name='order' value='asc' id='ewd-ufaq-order' \/>\n<input type='hidden' name='post_count' value='-1' id='ewd-ufaq-post-count' \/>\n<input type='hidden' name='current_url' value='\/fr\/wp-json\/wp\/v2\/ufaq\/7663' id='ewd-ufaq-current-url' \/>\n\t\n\t\n\t<div class='ewd-ufaq-faqs'>\n\n\t\t<div  class=\"ewd-ufaq-faq-div ewd-ufaq-faq-column-count-two ewd-ufaq-faq-responsive-columns-1 ewd-ufaq-faq-display-style-minimalist ewd-ufaq-can-be-toggled\" id='ewd-ufaq-post-7663-dXjf1sR7tM' data-post_id='7663'>\n\n\t\t\n\t<div class='ewd-ufaq-faq-title ewd-ufaq-faq-toggle'>\n\t\n\t<a class='ewd-ufaq-post-margin'  href='#' role=\"button\">\n\n\t\t<div class='ewd-ufaq-post-margin-symbol ewd-ufaq-square'>\n\t\t\t<span >B<\/span>\n\t\t<\/div>\n\n\t\t<div class='ewd-ufaq-faq-title-text'>\n\n\t\t\t<h5>\n\t\t\t\tEcart de vitesse entre lecture et enregistrement\t\t\t<\/h5>\n\n\t\t<\/div>\n\n\t\t<div class='ewd-ufaq-clear'><\/div>\n\n\t<\/a>\n\t\n<\/div>\n\t\n\t<div class='ewd-ufaq-faq-body' >\n\n\t\t\n\t\t\t\n\t\t\n\t\t\t\n\t\t\n\t\t\t<div class='ewd-ufaq-post-margin ewd-ufaq-faq-post'>\n\t<p>La technique des ESS Exponential Sine Sweeps de Angelo Farina est excellente pour certaines mesures acoustiques pour sa r\u00e9jection des bruits parasites. Mais quand les horloges du lecteur et de l'enregistreur ne sont pas synchrones, des probl\u00e8mes peuvent survenir, par exemple quand on lit avec un appareil diff\u00e9rent de l'enregistrement. Dans ce cas, la r\u00e9ponse impulsionnelle, \u00e0 l'\u00e9chelon, les spectrogrammes ou ondelettes peuvent \u00eatre erron\u00e9es (les mesures MMM ne sont pas affect\u00e9es heureusement). Pour \u00e9viter ces soucis, la version LA2v3 ajoute un signal de synchro en fin de lecture pour automatiquement compenser ces \u00e9carts. L'\u00e9cart du nombre d'\u00e9chantillons est indiqu\u00e9 en page p0. Si la diff\u00e9rence est inf\u00e9rieure \u00e0 2000ppm (200ppm est la sp\u00e9cification du Redbook CD), l'enregistrement est r\u00e9-\u00e9chantillonn\u00e9. Ceci correspond \u00e0 environ +-15630 \u00e9chantillons pour le fichier en st\u00e9r\u00e9o. Si l'\u00e9cart est sup\u00e9rieur \u00e0 2000ppm, ce n'est pas consid\u00e9r\u00e9 comme une diff\u00e9rence de fr\u00e9quence mais plut\u00f4t comme un probl\u00e8me d'enregistrement (dropout usb par exemple) et cet enregistrement n'est alors pas r\u00e9-\u00e9chantillonn\u00e9.<\/p>\n<\/div>\n\t\t\n\t\t\t<div class='ewd-ufaq-permalink'>\n\t\n\t<a href='https:\/\/www.loudspeakers.audio\/fr\/faqs\/clock-mismatch-between-player-and-recorder\/single-faq\/clock-mismatch-between-player-and-recorder\/'>\n\t\t\n\t\tPermalink\t\t\t\n\t<\/a>\n\n<\/div>\n\t\t\n\t\t\t\n\t\t\n\t\t\t\n\t\t\n\t\t\t<div class='ewd-ufaq-faq-custom-fields'>\n\n\t\n<\/div>\n\t\t\n\t\t\t\n\t\t\n\t\t\t\n\t\t\n\t\t\t\n\t\t\n\t<\/div>\n\n<\/div>\n\t<\/div>\n\n\t\n<\/div>","protected":false},"excerpt":{"rendered":"<p>B Clock mismatch between player and recorder Exponential sine sweeps (promoted by A. Farina) is a very nice technique to measure loudspeakers response with a good rejection of noises. But it may have problems when the player or recorder clock are unlocked (ie when you record on a computer that &hellip;<\/p>","protected":false},"author":1,"featured_media":0,"template":"","ufaq-category":[181],"ufaq-tag":[],"class_list":["post-7663","ufaq","type-ufaq","status-publish","hentry","ufaq-category-2-measurements"],"_links":{"self":[{"href":"https:\/\/www.loudspeakers.audio\/fr\/wp-json\/wp\/v2\/ufaq\/7663","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.loudspeakers.audio\/fr\/wp-json\/wp\/v2\/ufaq"}],"about":[{"href":"https:\/\/www.loudspeakers.audio\/fr\/wp-json\/wp\/v2\/types\/ufaq"}],"author":[{"embeddable":true,"href":"https:\/\/www.loudspeakers.audio\/fr\/wp-json\/wp\/v2\/users\/1"}],"wp:attachment":[{"href":"https:\/\/www.loudspeakers.audio\/fr\/wp-json\/wp\/v2\/media?parent=7663"}],"wp:term":[{"taxonomy":"ufaq-category","embeddable":true,"href":"https:\/\/www.loudspeakers.audio\/fr\/wp-json\/wp\/v2\/ufaq-category?post=7663"},{"taxonomy":"ufaq-tag","embeddable":true,"href":"https:\/\/www.loudspeakers.audio\/fr\/wp-json\/wp\/v2\/ufaq-tag?post=7663"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}