or output goes through FDN.</p>
  <p>It is useful to bypass FDN when checking the raw oscillator
  output.</p>
  </dd>
  <dt>Identity</dt>
  <dd>
  <p>Cross feedback amount between delays.</p>
  <p>When <code>Identitiy</code> is 0, feedback matrix becomes identity
  matrix. This means that it behaves as a bunch of comb filters.
  Increasing <code>Identity</code> means to increase cross feedback
  amount between delays. More cross feedback adds more non-integer
  harmonics, which sounds more metallic.</p>
  