\u7535\u5b50\u6280\u672f\u4e2d\u7684\u9891\u8c31\uff08\u5e45\u9891\u3001\u76f8\u9891\uff09\u5e38\u7528decade\u5bf9\u6570\u5750\u6807\uff0c\u6a2a\u8f74\u662f\u9891\u7387\u7684\u5bf9\u6570\u5750\u6807\uff0c\u7eb5\u8f74\u662f\u589e\u76ca\u7684dB\u8868\u793a\u3002<\/p>\n
\u8003\u8651\u5e45\u5ea6\u65f6\uff0c\u5e45\u503c\u589e\u76ca\u901a\u5e38$10\\log_{10}\\frac{a}{b}$<\/p>\n
\u7531\u4e8e\u529f\u7387\u662f\u5e45\u503c\u7684\u5e73\u65b9\uff0c\u529f\u7387\u589e\u76ca\u901a\u5e38 $10\\log_{10}\\frac{a^2}{b^2} = 20\\log_{10}\\frac{a}{b}$<\/p>\n
\u4e3e\u4f8b\uff0c\u5e38\u89c1\u76843dB\u70b9\uff0c$3dB = 10\\log_{10}\\frac{a^2}{b^2}$
\n$\\frac{a^2}{b^2} = 10^{\\frac{3}{10}} = 1.99526…$
\n\u529f\u7387\u53d8\u4e3a\u539f\u6765\u7684\u4e00\u534a\uff0c\u5e45\u503c\u53d8\u4e3a\u539f\u6765\u7684$\\sqrt{2}$\u500d<\/p>\n
\u53e6\u5916\u6709octave\u5bf9\u6570\u5750\u6807\uff0c\u5219\u662f\u501f\u7528\u97f3\u4e50\u4e2d\u7684\u516b\u97f3\u5ea6
\n$n=\\log_{2}(\\frac{f_1}{f_2})$
\n\u5f53$ n=1 $\uff0c\u4e3a\u516b\u97f3\u5ea6<\/p>\n
\u5341\u4e8c\u5e73\u5747\u5f8b\uff0c\u5c06\u516b\u5ea6\u97f3\u7684\u9891\u7387\u5206\u4e3a\u5341\u4e8c\u7b49\u5206\uff0c\u5373\u662f\u5206\u4e3a\u5341\u4e8c\u4e2a\u7b49\u6bd4\u7ea7\u6570\uff0c\u4e5f\u5c31\u662f\u6bcf\u4e2a\u97f3\u7684\u9891\u7387\u4e3a\u524d\u4e00\u4e2a\u97f3\u76842\u768412\u6b21\u65b9\u6839\uff08$\\sqrt[12]{2} = 2^{1\/12}$\uff09<\/p>\n
20dB\/decade = approx. 6dB\/octave
\n10dB\/decade = approx. 3dB\/octave.<\/p>\n
\u53c2\u8003\uff1a \u7535\u5b50\u6280\u672f\u4e2d\u7684\u9891\u8c31\uff08\u5e45\u9891\u3001\u76f8\u9891\uff09\u5e38\u7528decade\u5bf9\u6570\u5750\u6807\uff0c\u6a2a\u8f74\u662f\u9891\u7387\u7684\u5bf9\u6570\u5750\u6807\uff0c\u7eb5\u8f74\u662f\u589e\u76ca\u7684dB\u8868\u793a\u3002 \u8003\u8651\u5e45\u5ea6 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[120,123,121,122],"class_list":["post-71","post","type-post","status-publish","format-standard","hentry","category-notes","tag-120","tag-123","tag-121","tag-122"],"_links":{"self":[{"href":"https:\/\/blog.francis67.cc\/index.php?rest_route=\/wp\/v2\/posts\/71","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.francis67.cc\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.francis67.cc\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.francis67.cc\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.francis67.cc\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=71"}],"version-history":[{"count":4,"href":"https:\/\/blog.francis67.cc\/index.php?rest_route=\/wp\/v2\/posts\/71\/revisions"}],"predecessor-version":[{"id":1373,"href":"https:\/\/blog.francis67.cc\/index.php?rest_route=\/wp\/v2\/posts\/71\/revisions\/1373"}],"wp:attachment":[{"href":"https:\/\/blog.francis67.cc\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=71"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.francis67.cc\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=71"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.francis67.cc\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=71"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n1 \u516b\u97f3\u5ea6<\/a>
\n2 \u4ec0\u4e48\u662f\u500d\u9891\u7a0b<\/a>
\n3 Decade(log scale)<\/a>
\n4 Octave<\/a>
\n5 dB\/dec \u4e0e dB\/oct<\/a>
\n6 \u5341\u4e8c\u5e73\u5747\u5f8b<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"