{"id":215,"date":"2013-10-13T14:03:29","date_gmt":"2013-10-13T21:03:29","guid":{"rendered":"http:\/\/www.earlevel.com\/main\/?p=215"},"modified":"2016-12-08T15:52:00","modified_gmt":"2016-12-08T23:52:00","slug":"biquad-calculator-v2","status":"publish","type":"post","link":"https:\/\/www.earlevel.com\/main\/2013\/10\/13\/biquad-calculator-v2\/","title":{"rendered":"Biquad calculator v2"},"content":{"rendered":"<div id=\"container-20131013\" style=\"width:600px; height:200px;\"><\/div>\n<style type=\"text\/css\">\ntable#EQcontrols {\n    background: transparent;\n    border: 0;\n    border-collapse: separate;\n    border-spacing: 0;\n}\ntable#EQcontrols td {\n    border: none;\n    white-space: nowrap;\n}\n<\/style>\n<form name=biquad_params>\n<table id=\"EQcontrols\">\n<tr>\n<td style=\"vertical-align:top\">Type:<select name=Type onchange=\"drawIt_biquad2()\"><option value=\"lowpass\">lowpass<\/option><option value=\"highpass\">highpass<\/option><option value=\"bandpass\">bandpass<\/option><option value=\"notch\">notch<\/option><option value=\"peak\">peak<\/option><option value=\"lowShelf\">low shelf<\/option><option value=\"highShelf\">high shelf<\/option><option value=\"one-pole lp\">one-pole lp<\/option><option value=\"one-pole hp\">one-pole hp<\/option><\/select><\/p>\n<td style=\"vertical-align:top\">\nPlot:<select name=PlotType onchange=\"drawIt_biquad2()\"><option value=\"linear\">linear<\/option><option value=\"log\">log<\/option><\/select>\n<\/td>\n<\/tr>\n<\/table>\n<\/form>\n<table id=\"EQcontrols\">\n<tr>\n<td>\n<input id=\"biquad_Fs\" name=\"Fs\" value=\"44100\" style=\"text-align:right;width:4em;margin: 0 6px 6px 0;\" type=\"text\" onchange=\"drawIt_biquad2()\" \/>Sample rate (Hz)\n<\/td>\n<\/tr>\n<tr>\n<td>\n<input id=\"biquad_Fc\" name=\"Fc\" value=\"10000\" style=\"text-align:right;width:4em;margin: 0 6px 6px 0;\" type=\"text\" onchange=\"drawIt_biquad2()\" \/>Fc (Hz)\n<\/td>\n<td>\n<input type=\"range\" min=\"20\" max=\"20000\" value=\"10000\" name=\"sliderFc\" id=\"sliderFc\" title=\"Test slider\" onchange='setit(\"sliderFc\", \"biquad_Fc\", 1)' oninput='setit(\"sliderFc\", \"biquad_Fc\", 1)'>\n<\/td>\n<\/tr>\n<tr>\n<td>\n<input id=\"biquad_Q\" name=\"Q\" value=\"0.7071\" style=\"text-align:right;width:4em;margin: 0 6px 6px 0;\" type=\"text\" onchange=\"drawIt_biquad2()\" \/>Q\n<\/td>\n<td>\n<input type=\"range\" min=\"100\" max=\"10000\" value=\"707\" name=\"sliderQ\" id=\"sliderQ\" title=\"Test slider\" onchange='setit(\"sliderQ\", \"biquad_Q\", 1000)' oninput='setit(\"sliderQ\", \"biquad_Q\", 1000)'>\n<\/td>\n<\/tr>\n<tr>\n<td>\n<input id=\"biquad_Gain\" name=\"Gain\" value=\"6.0\" style=\"text-align:right;width:4em;margin: 0 6px 6px 0;\" type=\"text\" onchange=\"drawIt_biquad2()\" \/>Gain (dB)\n<\/td>\n<td>\n<input type=\"range\" min=\"-30\" max=\"30\" value=\"0\" name=\"sliderGain\" id=\"sliderGain\" title=\"Test slider\" onchange='setit(\"sliderGain\", \"biquad_Gain\", 1)' oninput='setit(\"sliderGain\", \"biquad_Gain\", 1)'>\n<\/td>\n<\/tr>\n<tr>\n<td><\/td>\n<td>\n<textarea id=\"biquad_coefsList\" rows=\"5\" cols=\"32\" readonly=\"readonly\" ><\/textarea><\/td>\n<\/tr>\n<\/table>\n<p>Here&#8217;s an update of the biquad calculator. It adds one-pole highpass and lowpass filters, and frequency, Q, and gain sliders. The sliders cover the range of typical audio settings, and are valuable for getting a quick feel for how the filters respond. But for precise settings and a wider range of parameters, type settings into the edit fields. (For this reason, the connection between sliders and edit fields are one-way\u2014sliders update the edit fields, but changing the fields does not change the sliders positions accordingly.)<\/p>\n<p>Review the biquad direct forms <a href=\"\/main\/2003\/02\/28\/biquads\/\">here<\/a>; direct form I is best for fixed point processors, while direct for II transposed is best for floating point implementations.<br \/>\n<script type=\"text\/javascript\" src=\"\/scripts\/utils\/flotr2.min.js\"><\/script><script type=\"text\/javascript\" src=\"\/scripts\/widgets\/20131013\/biquads2.js\"><\/script><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Type:lowpasshighpassbandpassnotchpeaklow shelfhigh shelfone-pole lpone-pole hp Plot:linearlog Sample rate (Hz) Fc (Hz) Q Gain (dB) Here&#8217;s an update of the biquad calculator. It adds one-pole highpass and lowpass filters, and frequency, Q, and gain sliders. The sliders cover the range of &hellip; <a href=\"https:\/\/www.earlevel.com\/main\/2013\/10\/13\/biquad-calculator-v2\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[21,4,8,9,30],"tags":[],"_links":{"self":[{"href":"https:\/\/www.earlevel.com\/main\/wp-json\/wp\/v2\/posts\/215"}],"collection":[{"href":"https:\/\/www.earlevel.com\/main\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.earlevel.com\/main\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.earlevel.com\/main\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.earlevel.com\/main\/wp-json\/wp\/v2\/comments?post=215"}],"version-history":[{"count":3,"href":"https:\/\/www.earlevel.com\/main\/wp-json\/wp\/v2\/posts\/215\/revisions"}],"predecessor-version":[{"id":1100,"href":"https:\/\/www.earlevel.com\/main\/wp-json\/wp\/v2\/posts\/215\/revisions\/1100"}],"wp:attachment":[{"href":"https:\/\/www.earlevel.com\/main\/wp-json\/wp\/v2\/media?parent=215"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.earlevel.com\/main\/wp-json\/wp\/v2\/categories?post=215"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.earlevel.com\/main\/wp-json\/wp\/v2\/tags?post=215"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}