<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>moogladder2</title> <link rel="stylesheet" type="text/css" href="csound.css" /> <link rel="stylesheet" type="text/css" href="syntax-highlighting.css" /> <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /> <link rel="home" href="index.html" title="The Canonical Csound Reference Manual" /> <link rel="up" href="OpcodesTop.html" title="Orchestra Opcodes and Operators" /> <link rel="prev" href="moogladder.html" title="moogladder" /> <link rel="next" href="moogvcf.html" title="moogvcf" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">moogladder2</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="moogladder.html">Prev</a> </td> <th width="60%" align="center">Orchestra Opcodes and Operators</th> <td width="20%" align="right"> <a accesskey="n" href="moogvcf.html">Next</a></td> </tr> </table> <hr /> </div> <div class="refentry"> <a id="moogladder2"></a> <div class="titlepage"></div> <a id="IndexMoogladder2" class="indexterm"></a> <div class="refnamediv"> <h2> <span class="refentrytitle">moogladder2</span> </h2> <p>moogladder2 — Moog ladder lowpass filter. </p> </div> <div class="refsect1"> <a id="idm281472912490136"></a> <h2>Description</h2> <p> Moogladder2 is an new digital implementation of the Moog ladder filter based on the work of Antti Huovilainen, described in the paper "Non-Linear Digital Implementation of the Moog Ladder Filter" (Proceedings of DaFX04, Univ of Napoli). This implementation uses approximations to the tanh function and so is faster but less accurate than <span class="emphasis"><em>moogladder</em></span>. </p> </div> <div class="refsect1"> <a id="idm281472912498104"></a> <h2>Syntax</h2> <pre class="synopsis">asig <span class="command"><strong>moogladder2</strong></span> ain, kcf, kres[, istor]</pre> <pre class="synopsis">asig <span class="command"><strong>moogladder2</strong></span> ain, acf, kres[, istor]</pre> <pre class="synopsis">asig <span class="command"><strong>moogladder2</strong></span> ain, kcf, ares[, istor]</pre> <pre class="synopsis">asig <span class="command"><strong>moogladder2</strong></span> ain, acf, ares[, istor]</pre> </div> <div class="refsect1"> <a id="idm281472912422552"></a> <h2>Initialization</h2> <p> <span class="emphasis"><em>istor</em></span> --initial disposition of internal data space. Since filtering incorporates a feedback loop of previous output, the initial status of the storage space used is significant. A zero value will clear the space; a non-zero value will allow previous information to remain. The default value is 0. </p> </div> <div class="refsect1"> <a id="idm281472912420616"></a> <h2>Performance</h2> <p> <span class="emphasis"><em>asig</em></span> -- input signal. </p> <p> <span class="emphasis"><em>kcf</em></span>/<span class="emphasis"><em>acf</em></span> -- filter cutoff frequency </p> <p> <span class="emphasis"><em>kres</em></span>/<span class="emphasis"><em>ares</em></span> -- resonance, generally < 1, but not limited to it. Higher than 1 resonance values might cause aliasing, analogue synths generally allow resonances to be above 1. </p> </div> <div class="refsect1"> <a id="idm281472912416104"></a> <h2>Examples</h2> <p> Here is an example of the moogladder2 opcode. It uses the file <a class="ulink" href="examples/moogladder2.csd" target="_top"><em class="citetitle">moogladder2.csd</em></a>. </p> <div class="example"> <a id="idm281472912414312"></a> <p class="title"> <strong>Example 576. Example of the moogladder2 opcode.</strong> </p> <div class="example-contents"> <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p> <div class="refsect1"> <a id="idm281472736023336"></a> <pre class="programlisting"> <span class="nt"><CsoundSynthesizer></span> <span class="nt"><CsOptions></span> <span class="c1">; Select audio/midi flags here according to platform</span> -odac <span class="c1">;;;realtime audio out</span> <span class="c1">;-iadc ;;;uncomment -iadc if realtime audio input is needed too</span> <span class="c1">; For Non-realtime ouput leave only the line below:</span> <span class="c1">; -o moogladder2.wav -W ;;; for file output any platform</span> <span class="nt"></CsOptions></span> <span class="nt"><CsInstruments></span> <span class="vg">sr</span> <span class="o">=</span> <span class="mi">44100</span> <span class="vg">ksmps</span> <span class="o">=</span> <span class="mi">32</span> <span class="vg">nchnls</span> <span class="o">=</span> <span class="mi">2</span> <span class="vg">0dbfs</span> <span class="o">=</span> <span class="mi">1</span> <span class="kd">instr</span> <span class="nf">1</span> k<span class="n">fe</span> <span class="nb">expseg</span> <span class="mi">500</span><span class="p">,</span> <span class="nb">p3</span><span class="o">*</span><span class="mf">0.9</span><span class="p">,</span> <span class="mi">1800</span><span class="p">,</span> <span class="nb">p3</span><span class="o">*</span><span class="mf">0.1</span><span class="p">,</span> <span class="mi">3000</span> a<span class="n">sig</span> <span class="nb">buzz</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">100</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="mi">1</span> k<span class="n">res</span> <span class="nb">line</span> <span class="mf">.1</span><span class="p">,</span> <span class="nb">p3</span><span class="p">,</span> <span class="mf">.99</span> <span class="c1">;increase resonance</span> a<span class="n">fil</span> <span class="nb">moogladder2</span> a<span class="n">sig</span><span class="p">,</span> k<span class="n">fe</span><span class="p">,</span> k<span class="n">res</span> <span class="nb">outs</span> a<span class="n">fil</span><span class="p">,</span> a<span class="n">fil</span> <span class="kd">endin</span> <span class="nt"></CsInstruments></span> <span class="nt"><CsScore></span> <span class="nb">f</span> <span class="mi">1</span> <span class="mi">0</span> <span class="mi">4096</span> <span class="mi">10</span> <span class="mi">1</span> <span class="nb">i</span> <span class="mi">1</span> <span class="mi">0</span> <span class="mi">10</span> <span class="nb">e</span> <span class="nt"></CsScore></span> <span class="nt"></CsoundSynthesizer></span> </pre> </div> </div> </div> <p><br class="example-break" /> </p> </div> <div class="refsect1"> <a id="idm281472912410120"></a> <h2>Credits</h2> <p> </p> <table border="0" summary="Simple list" class="simplelist"> <tr> <td>Author: Victor Lazzarini</td> </tr> <tr> <td>Author: John ffitch</td> </tr> <tr> <td>April 2016</td> </tr> </table> <p> </p> <p>New in version 6.07</p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="moogladder.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="OpcodesTop.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="moogvcf.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">moogladder </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> moogvcf</td> </tr> </table> </div> </body> </html>