manual/include/waveform-display.html

<p>
  The display of <dfn>waveforms</dfn> (or, more correctly, <dfn>peak
  envelopes</dfn>, since the actual waveform is only visible at the highest
  zoom levels) is configurable via the <kbd
  class="menu">Edit &gt; Preferences &gt; Editor</kbd> dialog, to support
  different usecases and user preferences. The following options are
  available:
</p>
<dl class="wide-table">
  <dt>Show waveforms in regions</dt>
  <dd>By default, Ardour draws waveforms within audio regions. Disable this
  option to hide them.</dd>
  <dt>Waveform scale</dt>
  <dd>
    <dl>
      <dt>Linear</dt>
      <dd>This is the traditional <dfn>linear</dfn> (1:1) display of the
      peak envelope, or, at higher zoom levels, the individual samples.</dd>
      <dt>Logarithmic</dt>
      <dd>Alternatively, you can use a <dfn>logarithmic</dfn> display of the
      peak envelope. This will give you a better idea of program loudness (it is similar
      to dBs) and plot soft passages more clearly, which is useful for soft
      recordings or small track height.</dd>
    </dl>
  </dd>
  <dt>Waveform shape</dt>
  <dd>
    <dl>
      <dt>Traditional</dt>
      <dd>The <dfn>zero</dfn> line appears in the middle of the display and waveforms
      appear as positive and negative peaks above <em>and</em> below.</dd>
      <dt>Rectified</dt>
      <dd>The zero line appears at the bottom of the display and waveforms appear
      as absolute peaks <em>above</em> the line only.</dd>
    </dl>
  </dd>
</dl>