<?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>moogladder</title>
<link rel="stylesheet" href="csound.css" type="text/css" />
<meta name="generator" content="DocBook XSL Stylesheets V1.75.2" />
<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="moog.html" title="moog" />
<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">moogladder</th>
</tr>
<tr>
<td width="20%" align="left"><a accesskey="p" href="moog.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" title="moogladder">
<a id="moogladder"></a>
<div class="titlepage"></div>
<a id="IndexMoogladder" class="indexterm"></a>
<div class="refnamediv">
<h2>
<span class="refentrytitle">moogladder</span>
</h2>
<p>moogladder —
Moog ladder lowpass filter.
</p>
</div>
<div class="refsect1" title="Description">
<a id="id3038370"></a>
<h2>Description</h2>
<p>
Moogladder 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 is probably a more accurate digital representation of
the original analogue filter.
</p>
</div>
<div class="refsect1" title="Syntax">
<a id="id3038386"></a>
<h2>Syntax</h2>
<pre class="synopsis">asig <span class="command"><strong>moogladder</strong></span> ain, kcf, kres[, istor]</pre>
</div>
<div class="refsect1" title="Initialization">
<a id="id3038600"></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" title="Performance">
<a id="id3038618"></a>
<h2>Performance</h2>
<p>
<span class="emphasis"><em>asig</em></span> -- input signal.
</p>
<p>
<span class="emphasis"><em>kcf</em></span> -- filter cutoff frequency
</p>
<p>
<span class="emphasis"><em>kres</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" title="Examples">
<a id="id3039209"></a>
<h2>Examples</h2>
<p>
</p>
<div class="example">
<a id="id3039217"></a>
<p class="title">
<b>Example 378. Example</b>
</p>
<div class="example-contents">
<pre class="programlisting">
kfe <span class="opc">expseg</span> 500, p3<span class="op">*</span>0.9, 1800, p3<span class="op">*</span>0.1, 3000
kenv <span class="opc">linen</span> 10000, 0.05, p3, 0.05
asig <span class="opc">buzz</span> kenv, 100, sr<span class="op">/</span>(200), 1
afil <span class="opc">moogladder</span> asig, kfe, 1
<span class="opc">out</span> afil</pre>
</div>
</div>
<p><br class="example-break" />
</p>
</div>
<div class="refsect1" title="Credits">
<a id="id3039278"></a>
<h2>Credits</h2>
<p>
</p>
<table border="0" summary="Simple list" class="simplelist">
<tr>
<td>Author: Victor Lazzarini</td>
</tr>
<tr>
<td>January 2005</td>
</tr>
</table>
<p>
</p>
<p>New plugin in version 5</p>
<p>January 2005.</p>
</div>
</div>
<div class="navfooter">
<hr />
<table width="100%" summary="Navigation footer">
<tr>
<td width="40%" align="left"><a accesskey="p" href="moog.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">moog </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>
