<!-- Converted to DocBook/SGML by Kevin Conder -->
<refentry id="tonek">
  <refmeta>
    <refentrytitle>tonek</refentrytitle>
  </refmeta>
 
  <refnamediv>
    <refname>tonek</refname>
    <refpurpose>
      A first-order recursive low-pass filter with variable frequency response.
      <indexterm id="IndexTonek"><primary>tonek</primary></indexterm>
    </refpurpose>
  </refnamediv>
 
  <refsect1>
    <title>Description</title>
    <para>
      A first-order recursive low-pass filter with variable frequency response.
    </para>
  </refsect1>
 
  <refsect1>
    <title>Syntax</title>
    <synopsis>kr <command>tonek</command> ksig, khp [, iskip]</synopsis>
  </refsect1>
 
  <refsect1>
    <title>Initialization</title>
    <para>
      <emphasis>iskip</emphasis> (optional, default=0) -- 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.
    </para>
  </refsect1>
 
  <refsect1>
    <title>Performance</title>
    <para>
      <emphasis>kr</emphasis> -- the output signal at control-rate.
    </para>

    <para>
      <emphasis>ksig</emphasis> -- the input signal at control-rate.
    </para>

    <para>
      <emphasis>khp</emphasis> --  the response curve's half-power point, in Hertz. Half power is defined as peak power / root 2. 
    </para>

    <para>
      <emphasis>tonek</emphasis> is like <link linkend="tone"><citetitle>tone</citetitle></link> except its
output is at control-rate rather than audio rate.
    </para>
  </refsect1>

  <refsect1>
    <title>See Also</title>
    <para>
      <link linkend="areson"><citetitle>areson</citetitle></link>,
      <link linkend="aresonk"><citetitle>aresonk</citetitle></link>,
      <link linkend="atone"><citetitle>atone</citetitle></link>,
      <link linkend="atonek"><citetitle>atonek</citetitle></link>,
      <link linkend="port"><citetitle>port</citetitle></link>,
      <link linkend="portk"><citetitle>portk</citetitle></link>,
      <link linkend="reson"><citetitle>reson</citetitle></link>,
      <link linkend="resonk"><citetitle>resonk</citetitle></link>,
      <link linkend="tone"><citetitle>tone</citetitle></link>
    </para>
  </refsect1>
</refentry>
