<!-- Converted to DocBook/SGML by Kevin Conder -->
<refentry id="streson">
  <refmeta>
    <refentrytitle>streson</refentrytitle>
  </refmeta>
 
  <refnamediv>
    <refname>streson</refname>
    <refpurpose>
      A string resonator with variable fundamental frequency.
      <indexterm id="IndexStreson"><primary>streson</primary></indexterm>
    </refpurpose>
  </refnamediv>
 
  <refsect1>
    <title>Description</title>
    <para>
      An audio signal is modified by a string resonator with variable fundamental frequency.
    </para>
  </refsect1>
 
  <refsect1>
    <title>Syntax</title>
    <synopsis>ar <command>streson</command> asig, kfr, ifdbgain</synopsis>
  </refsect1>
 
  <refsect1>
    <title>Initialization</title>
    <para>
      <emphasis>ifdbgain</emphasis> -- feedback gain, between 0 and 1, of the internal delay line. A value close to 1 creates a slower decay and a more pronounced resonance. Small values may leave the input signal unaffected. Depending on the filter frequency, typical values are &gt; .9.
    </para>
  </refsect1>
 
  <refsect1>
    <title>Performance</title>
    <para>
      <emphasis>asig</emphasis> -- the input audio signal.
    </para>

    <para>
      <emphasis>kfr</emphasis> -- the fundamental frequency of the string.
    </para>

    <para>
      <emphasis>streson</emphasis> passes the input <emphasis>asig</emphasis> through a network composed of comb, low-pass and all-pass filters, similar to the one used in some versions of the Karplus-Strong algorithm, creating a string resonator effect. The fundamental frequency of the <quote>string</quote> is controlled by the k-rate variable <emphasis>kfr</emphasis>.This opcode can be used to simulate sympathetic resonances to an input signal.
    </para>

    <para>
      <emphasis>streson</emphasis> is an adaptation of the StringFlt object of the SndObj Sound Object Library developed by the author.
    </para>
  </refsect1>

  <refsect1>
    <title>Examples</title>
    <para>
      Here is an example of the streson opcode. It uses the files <ulink url="examples/streson.orc"><citetitle>streson.orc</citetitle></ulink> and <ulink url="examples/streson.sco"><citetitle>streson.sco</citetitle></ulink>.

      <example>
        <title>Example of the streson opcode.</title>

        <programlisting>
<inlinemediaobject>
            <imageobject>
              <imagedata fileref="examples/streson.orc" format="linespecific">
            </imageobject>
          </inlinemediaobject>
        </programlisting>

        <programlisting>
<inlinemediaobject>
            <imageobject>
              <imagedata fileref="examples/streson.sco" format="linespecific">
            </imageobject>
          </inlinemediaobject>
        </programlisting>
      </example>
    </para>
  </refsect1>
 
  <refsect1>
    <title>Credits</title>
    <para>
      <simplelist>
        <member>Author: Victor Lazzarini</member>
        <member>Music Department</member>
        <member>National University of Ireland, Maynooth</member>
        <member>Maynooth, Co. Kildare</member>
        <member>1998</member>
      </simplelist>
    </para>
    <para>Example written by &namekevin;.</para>

    <para>New in Csound version 3.494</para>
  </refsect1>
</refentry>
