{"id":1733,"date":"2016-09-11T00:37:16","date_gmt":"2016-09-11T04:37:16","guid":{"rendered":"http:\/\/scripts.mit.edu\/~zong\/wpress\/?p=1733"},"modified":"2016-09-11T17:19:07","modified_gmt":"2016-09-11T21:19:07","slug":"built-in-audio-variations","status":"publish","type":"post","link":"https:\/\/blog.yhuang.org\/?p=1733","title":{"rendered":"Built-in audio variations"},"content":{"rendered":"<p>In light of Apple&#8217;s removal of the 3.5mm jack (for which there is an <a href=\"http:\/\/www.slate.com\/articles\/technology\/future_tense\/2016\/09\/apple_s_airpods_aren_t_just_wireless_earbuds_they_re_the_future_of_computing.html\">excellent analysis<\/a>), I must say that there is something to be said for the inconsistency of analog audio output from built-in audio devices in laptops. Apparently there is quite a bit of variation that I hadn&#8217;t realized.<\/p>\n<p>I ran <a href=\"http:\/\/www.audiocheck.net\/soundtests_headphones.php\">this test<\/a> using two sets of fairly wideband headphones and got results that were consistent across headphones but different between an HP laptop and a MacBook. The headphones were rated, respectively: (1) 15 &#8211; 20,000 Hz, 47 \u03a9 input impedance; and (2) 15 &#8211; 24,000 Hz, 35 \u03a9 input impedance. On the HP laptop with <a href=\"https:\/\/www.reddit.com\/r\/audiophile\/comments\/2s9b2h\/pandora_one_and_a_dac_amplifier\/\">&#8220;IDT High Definition Audio&#8221; (92HD93 chip)<\/a>, I could hear a range from 30 Hz to 18 kHz. On the MacBook Pro with <a href=\"http:\/\/apple.stackexchange.com\/questions\/57186\/what-is-the-impedance-of-the-line-headphone-jack-on-macbook-pro-retina\">mid-2014 hardware<\/a>, I could hear a range from 20 Hz to 16 kHz. I was quite surprised at the magnitude of this difference. A headphone amplifier (e.g. one built into the headphones) driven by digital input would eliminate this difference.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In light of Apple&#8217;s removal of the 3.5mm jack (for which there is an excellent analysis), I must say that there is something to be said for the inconsistency of analog audio output from built-in audio devices in laptops. Apparently there is quite a bit of variation that I hadn&#8217;t realized. I ran this test [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[3210,1309,3208,3206,3211,3203,1311],"class_list":["post-1733","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-3-5mm","tag-apple","tag-headphones","tag-hp","tag-idt","tag-laptop","tag-macbook"],"_links":{"self":[{"href":"https:\/\/blog.yhuang.org\/index.php?rest_route=\/wp\/v2\/posts\/1733","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.yhuang.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.yhuang.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.yhuang.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.yhuang.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1733"}],"version-history":[{"count":2,"href":"https:\/\/blog.yhuang.org\/index.php?rest_route=\/wp\/v2\/posts\/1733\/revisions"}],"predecessor-version":[{"id":1735,"href":"https:\/\/blog.yhuang.org\/index.php?rest_route=\/wp\/v2\/posts\/1733\/revisions\/1735"}],"wp:attachment":[{"href":"https:\/\/blog.yhuang.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1733"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.yhuang.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1733"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.yhuang.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1733"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}