 class="lineno">   85</span>&#160;</div><div class="line"><a name="l00086"></a><span class="lineno">   86</span>&#160;  <span class="comment">/** Set the centre or corner frequency of the filter.</span></div><div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;<span class="comment">  @param centre_freq 20 - 4096 Hz (AUDIO_RATE/4).</span></div><div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;<span class="comment">  This will be the cut-off frequency for L