Updated the Grid & Snap page.

[ardour-manual] / include / preferences.html

<p>
  Global <dfn>preferences</dfn> control general workflow and system
  configuration, and should apply to all sessions. They are located in <kbd
  class="menu">Edit &gt; Preferences</kbd> and stored in Ardour's <dfn>user
  configuration file</dfn> in the user's home directory.
</p>

<figure class="right">
  <img src="/images/preferences.png" alt="The Preferences window">
  <figcaption>
    The Preferences window
  </figcaption>
</figure>

<p>
        Preferences are conveniently grouped by category:
</p>

<ul>
        <li><a href="#preferences-general">General</a></li>
        <li><a href="#preferences-appearance">Appearance</a></li>
        <ul>
                <li><a href="#preferences-appearance-recorder">Recorder</a></li>
                <li><a href="#preferences-appearance-editor">Editor</a></li>
                <li><a href="#preferences-appearance-mixer">Mixer</a></li>
                <li><a href="#preferences-appearance-toolbar">Toolbar</a></li>
                <li><a href="#preferences-appearance-size-and-scale">Size and Scale</a></li>
                <li><a href="#preferences-appearance-colors">Colors</a></li>
                <li><a href="#preferences-appearance-quirks">Quirks</a></li>
                <li><a href="#preferences-appearance-translation">Translation</a></li>
        </ul>
        <li><a href="#preferences-editor">Editor</a></li>
        <ul>
                <li><a href="#preferences-editor-snap">Snap</a></li>
                <li><a href="#preferences-editor-modifiers">Modifiers</a></li>
        </ul>
        <li><a href="#preferences-midi">MIDI</a></li>
        <li><a href="#preferences-transport">Transport</a></li>
        <ul>
                <li><a href="#preferences-transport-chase">Chase</a></li>
                <li><a href="#preferences-transport-generate">Generate</a></li>
        </ul>
        <li><a href="#preferences-plugins">Plugins</a></li>
        <ul>
                <li><a href="#preferences-plugins-vst">VST</a></li>
                <li><a href="#preferences-plugins-audio_unit">Audio Unit</a></li>
        </ul>
        <li><a href="#preferences-monitoring">Monitoring</a></li>
        <li><a href="#preferences-signal_flow">Signal Flow</a></li>
        <li><a href="#preferences-metronome">Metronome</a></li>
        <li><a href="#preferences-control_surfaces">Control Surfaces</a></li>
        <li><a href="#preferences-metering">Metering</a></li>
        <li><a href="#preferences-performance">Performance</a></li>
        <li><a href="#preferences-video">Video</a></li>
</ul>

<h2 class="clear" id="preferences-general">General</h2>

<ul>  
  <li>
    <dfn>Audio/MIDI Setup</dfn>
    <ul>
          <li>
        <dfn>Show Audio/MIDI Setup window</dfn> Shows the
        <a href="@@audio-midi-setup">Audio/MIDI Setup</a> dialog.
      </li>
      <li>
        <dfn>Try to auto-launch audio/midi engine</dfn> allows Ardour to try to
        automatically launch the audio and MIDI system, driver and device, thus not
        showing the <a href="@@audio-midi-setup">Audio/MIDI Setup</a> dialog. This
        can save a little time if the system is always used the same way.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Editor Undo</dfn> defines the behaviour of the Undo operations:
    <ul>
      <li>
         <strong>Limit undo history</strong> sets how many commands can be
             undone using <kbd class="mod1">Z</kbd> or <kbd class="menu">Edit &gt; Undo</kbd>.
         Unchecking will keep an endless memory of operations to undo, at the
         expense of memory.
      </li>
      <li>
             <strong>Save undo history</strong> sets how many commands are saved so
             they are available to be undone after reopening the session. This can
         also be unchecked to keep all actions undoable, at the cost of bigger
         session files.
      </li>
      <li>
             <strong>Verify removal of last capture</strong> when enabled prompts to
             verify removal the last recording capture when
             <kbd class="menu">Edit &gt; Remove Last Capture</kbd> is executed.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Session Management</dfn>:
    <ul>
      <li>
        <strong>Make periodic backups of the session file</strong> will create
        a backup session file after changes to the timeline. The backup file is
        the session name followed by <em>.ardour.bak</em>. The backup can be
        used to recover from crashes when the session had not been explicitly
        saved.
      </li>
      <li>
        <strong>Default folder for new sessions:</strong> defaults the folder
        where Ardour will create new session folders. This is used in the
        <em>Session&nbsp;Setup</em> dialog displayed by
        <kbd class="menu">Session &gt; New</kbd>.
      </li>
      <li>
        <strong>Maximum number of recent sessions:</strong> determines how 
        many of the last opened sessions shows in the <em>Recent&nbsp;Sessions</em>
        dialog displayed by <kbd class="menu">Session &gt; Recent</kbd>.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Import</dfn>:
    <ul>
      <li>
        <strong>Drag and drop import always copies files to session</strong>
        selects, and then disables changes to, the <em>Copy files to session</em>
        option in the <a href="@@import-dialog">Add Existing Media</a> dialog.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Export</dfn>
    <ul>
      <li>
        <dfn>Save loudness analysis as image file after export</dfn> allows, when the
        <kbd class="option">Analyze Exported Audio</kbd> is checked in the
        <a href="@@export-dialog">Export dialog</a>, to save the analysis graph
        as a file named <code>session.png</code> alongside the exported audio
        file(s) (in the same folder).
      </li>
      <li>
        <dfn>Save Mixer screenshot after export</dfn> creates and exports
        a graphical image of the Mixer window as a file named
        <code>session-mixer.png</code> alongside the exported audio file(s)
        (in the same folder).
      </li>
    </ul>
  </li>
</ul>
  
<h2 id="preferences-appearance">Appearance</h2>

<ul>
  <li>
    <dfn>GUI Lock</dfn>
    <ul>
      <li>
        <dfn>Lock timeout (seconds):</dfn>locks the <abbr title="Graphical User
        Interface">GUI</abbr> after this many idle seconds (zero being 'never lock').
        The GUI can also be locked with <kbd class="menu">Session &gt; Lock</kbd>. When
        locked, a dialog will display a &quot;Click to unlock&quot; button.
      </li>
      <li>
        <dfn>System Screensaver Mode:</dfn>can be used to prevent the
        screensaver to be launched by the system, either while recording
        (e.g. for long and unattended recording session), when Ardour is
        simply started, or never (the screensaver is then able to start).
      </li>
    </ul>
  </li>
  <li>
    <dfn>Theme</dfn>
    <ul>
      <li>
        <dfn>Draw &quot;flat&quot; buttons</dfn>: when enabled, button controls
        in the user interface will be drawn with a flat look. When disabled button
        controls will have a slight 3D appearance.
      </li>
      <li>
        <dfn>Draw &quot;boxy&quot; buttons</dfn>: when enabled, button controls
        in the user interface will have square corners instead of being slightly
        rounded.
      </li>
      <li>
        <dfn>LED meter style</dfn> if checked, the bar meters in the editor and
        mixer will be styled to look like if they were made of LEDs, with a dotted
        bar. Unchecking this option makes the bars flat and continuous.
      </li>
      <li>
        <dfn>Icon Set:</dfn> Changes the mouse cursor icons used to indicate
        different tool modes in the editor. An example would be the icons used to
        indicate whether the cursor will select a region or change the length of a
        region.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Graphical User Interface</dfn>
    <ul>
      <li>
        <dfn>Highlight widgets on mouseover</dfn>, when checked, makes Ardour's
        widgets (buttons, sliders, &hellip;) slightly change color when the mouse
        hovers them, visually indicating what a mouse action would interact with.
      </li>
      <li>
        <dfn>Show tooltips if mouse hovers over a control</dfn> when checked,
        displays a little help bubble about the control the mouse hovers. The mouse
        pointer needs to stay idle for about 1 sec for the tooltip to appear.
      </li>
      <li>
        <dfn>Update clocks at TC Frame rate</dfn>: Ardour updates its clocks every
        100&nbsp;ms. Checking this will make the clock refresh at every TimeCode
        frame which is more responsive, at the cost of a bit more system stress.
      </li>
      <li>
        <dfn>Blink Rec-Arm buttons</dfn>: when enabled, the record-armed
        buttons on tracks will blink when they are armed but not currently recording.
        When disabled, the record-armed buttons on tracks will be outlined in red
        instead of blinking. The global record-arm button in the
        <a href="@@transport-bar">Transport bar</a> is unaffected.
      </li>
      <li>
        <dfn>Blink Alert indicators</dfn>: when enabled, the Alert indicators (like
        the <kbd class="menu">Error Log</kbd> or the <kbd class="menu">Feedback</kbd>
        button) will blink when they are active (when an error or feedback
        has been detected, respectively). When disabled, the indicators will turn red instead of
        blinking.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Graphics Acceleration</dfn>
    <ul>
          <li>
        <dfn>Disable Graphics Hardware Acceleration (requires restart)</dfn>
        Ardour uses hardware accelerated UI rendering by default for speed.
        Sometimes though, a buggy driver can cause this to make the system slow or
        unstable. Checking this will make Ardour draw its UI without
        hardware acceleration, in software, improving stability and responsiveness
        on those buggy systems at the expense of speed.
      </li>     
      <li>
        <dfn>Possibly improve slow graphical performance (requires restart)</dfn>
        Wherever gradients appear in the UI, Ardour uses hardware accelerated
        gradients creation. Checking this will make Ardour draw its own gradients without
        hardware acceleration for stability on systems with buggy drivers.
      </li>
    </ul>
  </li>
</ul>  
  
<h3 id="preferences-appearance-recorder">Recorder</h2>

<ul>
  <li>
    <dfn>Input Meter Layout</dfn>
    <ul>
      <li>
        <dfn>Input Meter Layout:</dfn>In Recorder mode, determines if audio
        inputs are displayed horizontally or vertically.
      </li>  
        </ul>
  </li>
</ul>
  
<h3 id="preferences-appearance-editor">Editor</h2>

<ul>
  <li>
    <dfn>General</dfn>
    <ul>
      <li>
        <dfn>Use name highlight bars in region displays (requires a restart)</dfn>:
        when enabled, the region name is displayed, in the editor, in its own opaque bar
        at the bottom of the region. When disabled, the region name is overlaid
        at the top of the region, possibly over audio waveforms or MIDI notes.
      </li>
      <li>
        <dfn>Region color follows track color</dfn>: when enabled,
        the background color of regions in the editor will be displayed using
        the color assigned to the track. When disabled the default region
        background color will be used.
      </li>
      <li>
        <dfn>Show Region Names</dfn>: when enabled, overlays the name of
        the region over its waveform representation, in the top-left. 
      </li>
       <li>
        <dfn>Waveforms color gradient depth:</dfn> determines how much gradient
        effect is applied to the inner of audio waveforms displayed in the editor.
        Values range from 0.0, no gradient effect, to 1.0, maximum effect.
      </li>
      <li>
        <dfn>Timeline item gradient depth:</dfn> Determines how much
        gradient effect is applied to the backgrounds of regions displayed in the
        editor. Values range from 0.0, no gradient effect, to 1.0, maximum effect.
      </li>
      <li>
        <dfn>Track name ellipsis mode:</dfn> when the track header is not 
        wide enough to display the track's name in full, selects how the
        name will be shorten between:
        <ul>
                  <li><em>Ellipsize start of name</em> will show only the end of the name</li>
                  <li><em>Ellipsize middle of name</em> will show only the start and end of the name</li>
                  <li><em>Ellipsize end of name</em> will show only the start of the name</li>
        </ul>
      </li>
      <li>
        <dfn>Add a visual gap below Audio Regions:</dfn> selects whether or
        not the audio regions fit the height of the track or leave a gap at
        the bottom, either small or large.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Waveforms</dfn>
    <ul>
      <li>
        <dfn>Show waveforms in regions</dfn> when enabled shows a visual
        representation of the region's audio waveform.
      </li>
      <li>
        <dfn>Show waveform while recording</dfn> when
        enabled, will draw the audio waveform in regions being recorded, in near
        real time. When disabled, only a region block will be drawn while recording,
        reducing CPU requirements.
      </li>
      <li>
        <dfn>Show waveform clipping</dfn>: when enabled the waveform
        displayed will show peaks marked in red if they exceed the clip level.
      </li>
      <li>
        <dfn>Waveform Clip Level (dBFS):</dfn> sets the level at which the
        waveform shown in an audio region will be drawn in red to indicate
        clipping. Setting lower than 0.0&nbsp;dBFS can be useful if any tool in
        the audio chain has problems near 0.0&nbsp;dBFS.
      </li>
      <li>
        <dfn>Waveform scale:</dfn> when waveforms are shown in audio regions,
        they can be displayed using a <em>linear</em> or a <em>logarithmic</em>
        scale. See <a href="@@waveform-display">Waveform display</a>.
      </li>
      <li>
        <dfn>Waveform shape:</dfn> when waveforms are shown in audio regions,
        they can be displayed using a <em>traditional</em> or a <em>rectified</em>
        shape. See <a href="@@waveform-display">Waveform display</a>.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Editor Meters</dfn>
    <ul>
      <li>
        <dfn>Show meters in track headers</dfn>, when enabled, shows
        a small meter in the Editor's <a href="@@audio-track-controls">track headers</a>.
        The meter is shown on the right side area of the header and provides an
        instant, if unprecise, view of the levels on this track/bus.
      </li>
      <li>
        <dfn>Limit track header meters to stereo</dfn>: if a track has more than
        two outputs (e.g. with a drum plugin), limits the number of meters in the
        track header to the first two ones. Only affects audio meters, not MIDI.
      </li>
    </ul>
  </li>
  <li>
    <dfn>MIDI Regions</dfn>
    <ul>
      <li>
        <dfn>Display first MIDI bank/program as 0</dfn>: when patches and bank changes
        are displayed in the editor, if this option is checked, the numbering will
        be zero-based instead of one-based, i.e. banks/programs will be numbered
        O, 1 ,2&hellip; instead of 1, 2, 3&hellip;
      </li>
      <li>
        <dfn>Don't display periodic (MTC, MMC) SysEx messages in MIDI Regions</dfn>:
        if checked, will hide these control messages from the MIDI regions for better
        legibility.
      </li>
      <li>
        <dfn>Show velocity horizontally inside notes</dfn>: when on, each note
        of a MIDI region (in <em>Sustained</em> mode) displays its velocity
        (0-127) with a darker fill proportional to its value.
      </li>
      <li>
        <dfn>Use colors to show note velocity</dfn>: if checked, makes the
        saturation of the notes color proportional to its velocity, hence making
        a more veloce note more intense in color.
      </li>
    </ul>
  </li>
</ul>
  
<h3 id="preferences-appearance-mixer">Mixer</h3>

<ul>
  <li>
    <dfn>Mixer Strip</dfn>
    <ul>
      <li>
        This table enables (checked) or disables (unchecked) the display of controls
        in the <a href="@@audiomidi-mixer-strips">mixer strip</a>. Controls whose
        display can be toggled are:
        <strong>Input</strong>, <strong>Phase&nbsp;Invert</strong>,
        <strong>Record&nbsp;&amp;&nbsp;Monitor</strong>, <strong>Solo&nbsp;Iso/Lock</strong>,
        <strong>Output</strong>, <strong>Comments</strong> and VCA Assigns.
      </li>
      <li>
        <dfn>Use narrow strips in the mixer for new strips by default</dfn> When
        enabled, new mixer strips are created in narrow format. When disabled,
        they are created in wide format. Existing mixer strips width can be toggled
        with the width control at the top left of the mixer strip.
      </li>
      <li>
        <dfn>Limit inline-mixer-strip controls per plugin :</dfn> Whether or
        not, and how many, controls each plugin can show in the mixer strip.
        These mixer-strip controls are added by checking <em>plugin context-menu
        &gt; Controls &gt; &square; control parameter</em>.
      </li>
    </ul>
  </li>
</ul> 
  
<h3 id="preferences-appearance-toolbar">Toolbar</h3>

<ul>
  <li>
    <dfn>Main Transport Toolbar Items</dfn>: this section allows to toggle the
    visibility of some elements of the main toolbar:
    <ul>
      <li>
        <dfn>Display Record/Punch Options</dfn> toggles the visibility of the
        <a href="@@selection-and-punch-clocks#punch_controls">punch and record</a> slice of
        the main toolbar.
      </li>
      <li>
        <dfn>Display Latency Compensation Info</dfn> toggles the visibility of the
        Latency Compensation slice of the main toolbar.
      </li>
      <li>
        <dfn>Display Secondary Clock</dfn> toggles the visibility of the
        <a href="@@transport-clocks">secondary clocks</a> slice of
        the main toolbar.
      </li>
      <li>
        <dfn>Display Selection Clock</dfn> toggles the visibility of the
        <a href="@@selection-and-punch-clocks#selection_clocks">selection clocks</a> slice of
        the main toolbar.
      </li>
      <li>
        <dfn>Display Monitor Section Info</dfn> toggles the visibility of the
       Monitor Info slice of the main toolbar.
      </li>
      <li>
        <dfn>Display Navigation Timeline</dfn> toggles the visibility of the
        <a href="@@mini-timeline">navigation/mini timeline</a> slice of
        the main toolbar.
      </li>
      <li>
        <dfn>Display Master Level Meter</dfn> toggles the visibility of the
        <a href="@@other-toolbar-items#mode_selector">selection clocks</a> slice of
        the main toolbar.
      </li>
    </ul>
  </li>
  <li>
        <dfn>Display Action-Buttons</dfn>
          <ul>
            <li>
                  <dfn>Column <em>n</em></dfn> enables or disables the visibility
              of the six possible columns of <a href="@@other-toolbar-items#mode_selector">Lua script buttons</a>.
          Each columns contains two user-assignable buttons.
        </li>
      </ul>
  </li>
</ul>  
  
<h3 id="preferences-appearance-size-and-scale">Size and Scale</h3>

<ul>
  <li>
    <dfn>User Interface Size and Scale</dfn>
    <ul>
          <li>
            <dfn>GUI and Font scaling:</dfn> allows the display size of most of the
            text and buttons in the user interface to be scaled up or down. May
            require a restart to take effect.
      </li>
    </ul>
  </li>
</ul>
  
<h3 id="preferences-appearance-colors">Colors</h3>
 
<ul>
  <li>
    <dfn>Colors</dfn>
    <ul>
      <li>
        <dfn>Color Theme</dfn> allows to switch between some presets bundled with
        Ardour, changing both the palette and items colors, hence styling Ardour
        all at once.
      </li>
      <li>
        The table allows to change the color settings in Ardour by acting on three
        parameters:
        <ul>
          <li>
            <dfn>Items</dfn> that allow to choose any color from the palette (see below)
            to color a UI element. Clicking on a color sample in the <strong>Color</strong>
            column bring up the Palette, to choose from.
          </li>
          <li>
            <dfn>Palette</dfn> that allows to create a set of colors that will be used
            in the UI. Using a palette allows for better consistency, instead of
            picking "free" colors for each UI element. Clicking on a color patch brings
            up a full color selector, to assign this color to this patch of the palette.
          </li>
          <li>
            <dfn>Transparency</dfn> where possible, allows to select, with a slider,
            the transparency of the UI element, with 0 (slider to the left) being
            fully opaque.
          </li>
        </ul>
      </li>
      <li>
        <dfn>Restore Defaults</dfn> turns all the palette, item colors and transparency
        back to Ardour's default base setting, in case Ardour's appearance has turned
        into a toddler's toy.
      </li>
    </ul>
  </li>
</ul>
 
<h3 id="preferences-appearance-quirks">Quirks</h3>

<ul>
  <li>
    <dfn>Various Workarounds for Windowing Systems</dfn>: As Ardour is available
    on a number of platforms and windowing systems, some specific workarounds are
    sometimes required to provide a smooth experience to the user.
    <ul>
      <li>
        <dfn>Use visibility information provided by your Window Manager/Desktop</dfn>
        allows the system window manager's rules for the windows visibility to
        supersede Ardour's.
      </li>
      <li>
        <dfn>All floating windows are dialogs</dfn>: when enabled, Ardour will
        use type &quot;Dialog&quot; for all floating windows instead of using type
        &quot;Utility&quot; for some of them. This may help usability with some
        window managers. This setting requires a restart of Ardour to take effect.
      </li>
      <li>
        <dfn>Transient windows follow front window.</dfn>: when enabled,
        transient windows will follow the front window when toggling between the
        editor and mixer. This setting requires a restart of Ardour to take effect.
      </li>
      <li>
        <dfn>Float detached monitor-section window</dfn>: as the <a href="@@monitor-section">
        monitor section</a> can be detached from the mixer, this option makes it a
        floating window, which may be handled differently by the windowing system
        and easier to access.
      </li>
    </ul>
  </li>
</ul>  
 
<h3 id="preferences-appearance-translation">Translation</h3>

<ul>
  <li>
    <dfn>Internationalization</dfn>
    <ul>
      <li>
        <dfn>Use translations</dfn> sets if Ardour should use a translated
        version of all the messages. The default (unchecked) is English (US). When
        checked, and if a language file exists for the system language, this file
        will be used to translate Ardour.
      </li>
    </ul>
  </li>
</ul>    
      
<h2 id="preferences-editor">Editor</h2>
     
<ul>
  <li>
        <dfn>Region Information</dfn>      
        <ul>
          <li>
        <dfn>Show xrun markers in regions</dfn> puts a marker on the region(s)
        while recording, when a buffer over/underflow happens.
      </li>      
      <li>
        <dfn>Show cue markers in regions</dfn> determines if cue markers,
        that are bounded to regions, are displayed or not.
      </li>  
      <li>
        <dfn>Show gain envelopes in audio regions:</dfn> sets in which
        <a href="@@toolbox">modes</a> the gain envelope is displayed in audio regions.
        The gain envelope is superimposed over the region in the selected modes, and
        hidden otherwise for a better legibility.
      </li>
    </ul>   
  </li>
  <li>
        <dfn>Scroll and Zoom Behaviors</dfn>      
        <ul>   
      <li>
        <dfn>Zoom to mouse position when zooming with scroll wheel</dfn>: by default,
        Ardour zooms to the <a href="@@edit-point-control">edit point</a>. When this
        option is checked, and the zoom is done with <kbd class="mod1n"></kbd> + mousewheel,
        the zoom will happen at the mouse cursor position regardless of the edit point
        chosen.
      </li>
      <li>
        <dfn>Zoom with vertical drag in rulers</dfn> allows, when checked, to click
        anywhere in an empty zone of the <a href="@@ruler">ruler</a> zone and drag
        up to zoom in or down to zoom out.
      </li>
      <li>
        <dfn>Double click zooms to selection</dfn> allows by double clicking, to zoom
        on the selection, both on the time and tracks axes. If the selection has been
        done with <kbd class="mod1n"></kbd> or <kbd class="mod3n"></kbd>, then this
        key should still be pressed when double clicking for this to work, otherwise
        the first click breaks the group selection.
      </li>
      <li>
        <dfn>Update editor window during drags of the summary</dfn>: when
        enabled the contents of the editor window will redraw the tracks area
        as the selection rectangle in the <a href="@@summary">summary</a> area is
        moved or resized.
      </li>
      <li>
        <dfn>Auto-scroll editor window when dragging near its edges</dfn>
        when enabled will scroll the editor window automatically when dragging a
        region. This can make it easier to see where to position the region.
      </li>    
      <li>
        <dfn>Auto-scroll speed when dragging playhead:</dfn> chooses how fast the canvas
        scrolls when dragging the playhead outside of the visible canvas.
      </li>
      <li>
        <dfn>Limit zooming &amp; summary view to X minutes beyond session extents:</dfn>
        prevents the zoom out both in the editor and the summary, to show anything past
        the chosen time after the end marker, restraining the vision to only useful
        content.
      </li>
    </ul>
  </li>
  <li>
        <dfn>Editor Behaviour</dfn>      
        <ul>
          <li>
        <dfn>Move relevant automation when audio regions are moved</dfn>,
        when enabled, causes automation data to stay with a region when the
        region is moved inside the playlist. When disabled, the automation is
        not affected by movement of regions.
      </li>
      <li>
        <dfn>Ignore Y-axis click position when adding new automation-points</dfn>
        allows to create new automation points at the x-position of the mouse, without
        using the Y-position as the value, hence creating a new automation point at
        its present value.
      </li>
      <li>
                <dfn>Automation edit cancels auto hide</dfn> determines wether automation
                lanes that have been automatically shown because of the 
                <kbd class="option">Edit &gt; Show Automation Lane on Touch</kbd>
                option should be kept visible if the automation has been touched.
      </li>
      <li>
        <dfn>Default fade shape:</dfn> sets which <a href="@@create-region-fades-and-crossfades">
        fade shape</a> is the default.
      </li>
      <li>
        <dfn>Regions in active edit groups are edited together:</dfn> sets
        the criteria to see if editing actions apply to tracks grouped together
        in an group.
      </li>
      <li>
        <dfn>Layering model:</dfn> Ardour allows <a href="@@layering-display">layering</a>
        multiple regions in the same track. This selector defines how these layers are
        managed, either manually or by placing the latest on top.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Split/Separate</dfn>
    <ul>
      <li>
        <dfn>After a Separate operation, in Range mode:</dfn> determines what
        should become of the Range selection after a Separate operations:
        <ul>
                        <li>Clear the Range Selection: nothing is selected anymore</li>
                        <li>Preserve the Range Selection: the range selection is kept</li>
                        <li>Force-Select the regions under the range: the regions that
                        were in the range selection are selected in Grab/Object mode</li>
        </ul>
      </li>
      <li>
        <dfn>After a Split operation, in Object mode:</dfn> determines which,
        if any, regions are selected after a split operation. The options are:
        <ul>
                        <li>Clear the Region Selection: nothing is selected anymore</li>
                        <li>Select only the newly-created regions BEFORE the split point:
                        </li>if regions have been affected by the split, then the regions
                        created by the split before the split point is selected
                        <li>Select only the newly-created regions BEFORE the split point:
                        same as above, for the regions created after the split point</li>
                        <li>Select the newly-created regions: sum of the two above, i.e. all
                        the regions that are created as a result of the split are selected.</li>
                        <li>Preserve the existing selection, AND select all newly-created regions:
                        same as above (all the parts that have been created by the split) plus
                        the unaffected regions that were selected before the split.</li>
        </ul>
      </li>
    </ul>
  </li>
</ul>

<h3 id="preferences-editor-snap">Snap</h3>

<ul>
  <li>
        <dfn>General Snap options:</dfn>      
        <ul>
          <li>
        <dfn>Snap Threshold (pixels):</dfn> is the maximum distance between
        a snap anchor and an object for Ardour to force the object to be
        placed precisely at that anchor.
      </li> 
          <li>
        <dfn>Approximate Grid/Ruler granularity (pixels):</dfn> Ardour tries
        to show a reasonable number of grid lines at the current zoom level
        and in the available screen estate. This value tells Ardour what the
        approximate absolute distance between two closest grid lines should
        be, so that it displays the most relevant grid scale to approximately
        fit this distance.
      </li> 
          <li>
        <dfn>Show "snapped cursor"</dfn> If the Edit point is not the playhead,
        shows the currently selected Edit point as a blue line, to indicate
        where the next editing operation will occur.
      </li>
      <li>
        <dfn>Snap rubberband selection to grid</dfn> makes the highlighted 
        zone created by an area selection also snap to grid, i.e. the beginning
        and end of the resulting selecting box will both be grid anchors.
      </li>
      <li>
        <dfn>Grid switches to alternate selection for Internal Edit Tools</dfn>
        Two levels of grid mode can coexist in Ardour, one for global regions
        manipulations, and one for finer, in-region editing (e.g. for placing
        MIDI events in a MIDI region). When this option is checked, entering
        Internal Edit mode makes the grid mode switch from one mode to the other.
      </li>
      <li>
        <dfn>Rulers automatically change to follow the Grid mode selection</dfn>
        If enabled, changing the Grid mode also makes the relevant
        <a href="@@ruler">ruler</a> visible, while hiding the other ones.
      </li>
    </ul>
  </li>
  <li>
        <dfn>When "Snap" is enabled, snap to:</dfn>      
        Lists the different possible anchors to which an object should snap to, among:
        <ul>
          <li>Markers</li>
          <li>Region Sync points</li>
          <li>Region Starts</li>
          <li>Region Ends</li>
          <li>Grid</li>
        </ul>
  </li>
</ul>
      
<h3 id="preferences-editor-modifiers">Modifiers</h3>

<p>
  This page allows to choose how things are done in the editor. This is a very
  flexible way for Ardour to match an existing workflow, or speed up the editing
  process based on the user's most used actions.
</p>
<p>
  The <kbd class="menu">Reset to recommended defaults</kbd> button at the bottom
  provides a way to revert any user made change to its default value.
</p>
      
<h2 id="preferences-midi">MIDI</h2>

<ul>
  <li>
    <dfn>Session</dfn>
    <ul>
          <li>
        <dfn>Allow non quarter-note pulse</dfn>: by default, Ardour understands the <a
        href="@@tempo-and-meter">tempo</a> as the number of quarter notes in a minute.
        Checking this option allows to set the tempo based on any division of the note,
        from whole to 1/128th. This is reflected in the <kbd class="menu">Edit
        Tempo</kbd> window (accessed by double clicking a tempo marker) that shows a
        "Pulse" menu when this option is checked.
      </li>     
      <li>
        <dfn>Initial program change:</dfn> Ardour will send a MIDI program
        change message on the <code>ardour:MMC out</code> MIDI port when a session
        is loaded and whenever this field is changed. A value of -1 means don't
        send any program change message.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Audition</dfn>
    <ul>
      <li>
        <dfn>Sound MIDI notes as they are selected in the editor</dfn> will play
        any selected or added MIDI note when in Draw or Internal Edit modes. The
        note is sent as MIDI as if Ardour was playing it withe the session, so the
        processors and signal routing will be applied.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Virtual Keyboard</dfn>
    <ul>
      <li>
        <dfn>Virtual Keyboard Layout:</dfn> selects which (if any) computer
        keyboard layout is used to be mapped on the keys of the musical
        keyboard of the Virtual Keyboard (<kbd class="menu">Window &gt; Virtual Keyboard</kbd>).
      </li>

    </ul>
  </li>
  <li>
    <dfn>MIDI Port Options</dfn>
    <ul>
      <li>
        <dfn>MIDI input follows MIDI track selection</dfn> allows Ardour to automatically
        connect the MIDI input to the selected track. Selecting a different MIDI
        track results in Ardour disconnecting the MIDI device from the former track
        and connecting it to the newly selected one, so that the MIDI device is
        always connected to the selected track. Which MIDI device will follow
        selection can be chosen below.
      </li>
    </ul>
  </li>
</ul>      
  
<h2 id="preferences-transport">Transport</h2>

<ul>
  <li>
    <dfn>General</dfn>
    <ul>
      <li>
        <dfn>Prompt for new marker names</dfn> when enabled, popup a dialog
        when a new <a href="@@working-with-markers">marker</a> is created. This allows
        markers to be named as they are created.
      </li>             
      <li>
        <dfn>Stop at the end of the session</dfn> causes the transport to
        stop during playback when it reaches the end marker. Behavior during
        recording is not changed.
      </li>
      <li>
        <dfn>Keep record-enable engaged on stop</dfn> leaves the global
        record-enable engaged after transport is stopped.  Does not affect track
        level record-enable which is never changed on stop.
      </li>
      <li>
        <dfn>Reset default speed on stop</dfn> when the 
        <a href="@@transport-bar">Shuttle speed control</a> is in <em>wheel</em>
        mode, i.e. the transport speed can be constantly changed, enabling this
        option makes these changes temporary, and the transport speed reset
        each time the transport is stopped.      
      </li>
      <li>
        <dfn>Disable per-track record disarm while rolling</dfn>, when
        enabled, will not allow the any track's record-enable to be disarmed
        during record, preventing accidentally stopping the recording of a take.
      </li>
      <li>
        <dfn>12dB gain reduction during fast-forward and fast-rewind</dfn>
        when enabled will reduce the unpleasant increase in perceived volume
        that occurs when fast-forwarding or rewinding through some kinds of audio.
      </li>
      <li>
        <dfn>Rewind/Fast-forward buttons change direction immediately</dfn>
        sets wether Rewind and Fast-forward transport operations
        (<kbd class="menu">Transport &gt; Forward/Rewind</kbd>) changes the 
        playback direction and speed abruptly, or gradually.
      </li>
      <li>
        <dfn>Allow auto-return after rewind/ffwd operations</dfn>
        if <a href="@@other-toolbar-items#playhead_options">Auto return</a>is engaged, sets wether
        it applies to rewind and fast-forward operations.
      </li>
      <li>
        <dfn>Preroll:</dfn> sets the duration of the preroll for playing and
        recording when using a preroll. Can be a musical duration (in bars) or a
        duration in seconds.
      </li>
    </ul>
  </li>  
  <li>
    <dfn>Looping</dfn>
    <ul>
      <li>
        <dfn>Play loop is a transport mode</dfn> changes the behavior of the
        loop button, turning it into a toggle. When enabled, the loop button does
        not start playback but forces playback to always play the loop. Looping
        stays engaged when the transport is stopped. Playback continues where the
        transport stopped and continues to loop. When disabled, the loop button
        starts playing the loop but stop then cancels loop playback.
      </li>
      <li>
        <dfn>Loop Fades:</dfn> when the transport moves from the end of the loop
        range back to the beginning, clicks might be audible. This parameter
        allows for adding fades (in, out or cross-) to prevent those clicks.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Dropout (xrun) Handling</dfn>
    <ul>
      <li>
        <dfn>Stop recording when an xrun occurs</dfn> will stop the transport
        when an xrun occurs during recording, ensuring no audible glitches are
        recorded.
      </li>
      <li>
        <dfn>Create markers where xruns occur</dfn> will create a new
        <a href="@@working-with-markers">marker</a> when an xrun occurs during
        recording at the location of the xrun. This marks where possible xruns
        might produce audible glitches.
      </li>
      <li>
        <dfn>Reset x-runs counter when starting to record</dfn>, when enabled,
        sets the x-run counter in the <a href="@@status-bar">Status bar</a>
        to 0 each time a recording is started, hence showing only the relevant
        number of x-run while recording.
      </li>
    </ul>
  </li>
  <li>
        <dfn>Plugins</dfn>
    <ul>  
          <li>
        <dfn>Silence plugins when the transport is stopped</dfn> when stopping
        playback or recording, if this option is checked, the plugins that still
        emit sound (reverbs, etc&hellip;) will be stopped. If unchecked, the plugins
        will continue playing after the transport stop.
      </li>
        </ul>
  </li>
</ul>  
  
<h3 id="preferences-transport-chase">Chase</h3>

<ul>
  <li>
    <dfn>MIDI Machine Control (MMC)</dfn>
    <ul>
      <li>
        <dfn>Respond to MMC commands</dfn> when enabled Ardour will respond
        to MIDI Machine Control commands received on the <code>ardour:MMC in</code>
        MIDI port.
      </li>  
      <li>
        <dfn>Inbound MMC device ID:</dfn> is the only device ID Ardour will
        respond to when an MMC command is received on the <code>ardour:MMC in</code>
        MIDI port.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Transport Masters</dfn>
    <ul>
          <li>
                <dfn>Show Transport Master Window</dfn> Opens the Transport masters
                window, where all the timecode sources are shown to be selected
                and/or synchronized; same as clicking <kbd class="menu">Window &gt;
                Transport Masters</kbd>
          </li>
      <li>
                <dfn>Match session video frame rate to external timecode</dfn>
                controls the value of the video frame rate <em>while chasing</em>
                an external timecode source. When enabled, the session video frame rate will be
                changed to match that of the selected external timecode source. When disabled,
                the session video frame rate will not be changed to match that of the selected
                external timecode source. Instead, the frame rate indication in the main clock
                will flash red and Ardour will convert between the external timecode standard
                and the session standard.
          </li>
    </ul>
  </li>
</ul>

<h3 id="preferences-transport-generate">Generate</h3>

<ul>
  <li>
    <dfn>Linear Timecode (LTC) Generator</dfn>
    <ul>
      <li>
        <dfn>Enable LTC generator</dfn> when enabled Ardour will
        output an LTC timecode signal on its <em>LTC-out</em> port.
        If this option is checked, the two options below are active:
      </li>
      <li>
        <dfn>Send LTC while stopped</dfn>, (only available when the previous
        <em>Enable LTC generator</em> is on) when enabled Ardour will
        continue to send LTC information even while the transport (playhead)
        is not moving.
      </li>
      <li>
        <dfn>LTC generator level [dBFS]:</dfn> specifies the peak volume of
        the generated LTC signal in dbFS. A good value is 0dBu&equals;&minus;18dbFS
        in an EBU calibrated system.
      </li>
      <li>
        <dfn>LTC Output Port:</dfn> selects to which port (if any) the
        LTC generator will be connected by default.
      </li>
    </ul>
  </li>
  <li>
    <dfn>MIDI Time Code (MTC) Generator</dfn>
    <ul>
      <li>
        <dfn>Enable MTC Generator</dfn> when enabled Ardour will generate MIDI
        time code on the <code>ardour:MTC out</code> MIDI port.
      </li>
      <li>
        <dfn>Max MTC varispeed (%):</dfn>
        MIDI time code generation will be disabled when the transport speed is
        greater than normal speed plus this percentage or less than normal minus
        this percentage.
      </li>
    </ul>
  </li>
  <li>
        <dfn>MIDI Machine Control (MMC)</dfn>
        <ul>
          <li>
        <dfn>Send MMC commands</dfn> when enabled Ardour will send MIDI Machine
        Control commands on the <code>ardour:MMC out</code>
        MIDI port.
      </li>
          <li>
        <dfn>Outbound MMC device ID:</dfn> is the MIDI device ID Ardour will
        use when it sends MMC commands.
      </li>
    </ul>
  </li>
  <li>
    <dfn>MIDI Beat Clock (Mclk) Generator</dfn>
    <ul>
      <li>
        <dfn>Enable Mclk generator</dfn> when enabled Ardour will generate a
        (tempo dependant) beat clock at a rate of 24 pulses per quarter note on
        the <code>ardour:MIDI clock out</code> port.
      </li>
    </ul>
  </li>
</ul>

<h2 id="preferences-plugins">Plugins</h2>

<p class="note">
  The content of this preference page varies heavily between versions or Ardour:
  both the platform and the build-time options can make Ardour support some types
  of plugins and not others. While this documentation tries to show all possible
  options, most systems will only show a subset of the options hereunder, e.g.
  AudioUnits are macOS only&hellip;
</p>

<ul>
  <li>
    <dfn>Scan/Discover</dfn>
    <ul>
      <li>
        <dfn>Scan for Plugins</dfn> will initiate an immediate scan of the system
        for available plugins. Useful to get a newly installed plugin recognised
        by Ardour.
      </li>
    </ul>
  </li>
  <li>
    <dfn>General</dfn>
    <ul>
      <li>
        <dfn>Always Display Plugin Scan Progress</dfn> When enabled a
        popup window showing plugin scan progress is displayed for indexing
        (cache load) and discovery (detect new plugins).
      </li>
      <li>
        <dfn>Make new plugins active</dfn> when enabled, any plugin added to a track
        will be in active mode. If unchecked, the plugins will be added in inactive
        mode by default, hence have no processing effect on the track/bus.
      </li>
    </ul>
  </li>
  <li>
    <dfn>LV1/LV2</dfn>
    <ul>
      <li>
        <dfn>Conceal LADSPA (LV1) Plugins if matching LV2 exists</dfn> When 
        enabled, gives precedence to the LV2 (more up-to-date) version of
        a plugin over its LV1 version, if both exists.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Plugin GUI</dfn>
    <ul>
      <li>
        <dfn>Automatically open the plugin GUI when adding a new plugin</dfn>
        shows the plugins GUI as soon as it is added to the processing box. If
        unchecked, the plugin will be added in the processor box but the GUI will
        only be shown when <kbd class="mouse">double clicking</kbd> it.
      </li>
      <li>
        <dfn>Show Plugin Inline Display on Mixer strip by default</dfn> allows Ardour
        to show, in the <a href="@@audiomidi-mixer-strips">mixer strips</a>, a
        visual rendering of the effect. These Inline Display are a special feature
        of Ardour, so not all plugins are able to show this display. Most of Ardour's
        <a href="@@plugins-bundled-with-ardour">own plugins</a> have an Inline Display.
        At any time, the plugin's Inline Display can be toggled on or off by
        <kbd class="mod3n"></kbd>double-clicking it.
      </li>
      <li>
        <dfn>Don't automatically open the plugin GUI when the plugin has an inline
        display mode</dfn>: this option, available only if
        <kbd class="option">Automatically open the plugin GUI when adding a new plugin</kbd>
        is checked, supercedes it and hides the plugin GUI at creation if it has an
        Inline Display, like Ardour's own <code>ACE *</code> plugins.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Instrument</dfn>
    <ul>
      <li>
        <dfn>Ask to replace existing instrument plugin</dfn>: if a MIDI track already
        has an instrument (i.e. MIDI to audio converter of some sort) and this
        option is checked, Ardour will detect it and offer to replace the existing
        instrument with the newly added one, avoiding a possible conflict.
      </li>
      <li>
        <dfn>Interactively configure instrument plugins on insert</dfn>: when inserting
        a multichannel instrument plugin, if this option is checked, prompts the
        user for the channel configuration for this plugin.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Statistics</dfn>
    <ul>
      <li>
        <dfn>Reset Statistics</dfn>: clears the statistics used to determine
        the most used and most recently used plugins.
      </li>
      <li> 
        <dfn>Plugin chart (use-count) length:</dfn> In the Mixer view's
        <a href="@@favorite-plugins-window">favorite plugins</a> section,
        determines how many plugins are displayed when in <em>Top-10 Plugins</em>
        mode. 
      </li>
      <li> 
        <dfn>Plugin recent list length:</dfn> Same as above,
        when in <em>Recent Plugins</em> mode. 
      </li>
    </ul>
  </li>
</ul>

<h3 id="preferences-plugins-vst">VST</h3>

<ul>
  <li>
    <dfn>VST</dfn>
    <ul>
      <li>
        <dfn>Enable Mac VST support (requires restart or re-scan)</dfn> makes a
        MacOs system able to run VST-Mac plugins. As stated, a new scan for plugins
        is required, be it manually or by restarting Ardour.
      </li>
      <li>
        <dfn>Scan for [new] VST Plugins on Application Start</dfn> When
          enabled new VST plugins are searched, tested and added to the cache
          index on application start. When disabled new plugins will only be
          available after triggering a 'Scan' manually.
      </li>
      <li>
        <dfn>Verbose Plugin Scan</dfn>: adds information about the plugin in the
        <a href="@@status-bar">Log window</a>.
      </li>
      <li>
        <dfn>Scan Time Out</dfn> Specifies the default timeout for plugin
          instantiation. Plugins that require more time to load will be
        blacklisted. A value of &infin; disables the timeout.
      </li>
    </ul>
  </li>
  <li>
    <dfn>VST 2.x</dfn>
    <ul>
      <li>
        <dfn>VST 2 Cache:</dfn> Clicking the <kbd class="menu">Clear</kbd> button
        removes all VST plugins from the list of plugins available to be
        inserted into the processor box. A new VST plugin scan is then required.
      </li>
      <li>
        <dfn>VST 2 Blacklist:</dfn> Clicking the <kbd class="menu">Clear</kbd>
        button makes blacklisted VST plugins available to be added to the processor
        box.
      </li>
      <li>
        <dfn>Linux VST2 Path:</dfn> Clicking the <kbd class="menu">Edit</kbd> button
        pops up a dialog to manage the directories that will be searched for Linux
        VST plugins. When modified, Ardour will offer to scan those paths for plugins.
      </li>
      <li>
        <dfn>Path:</dfn> are the paths chosen above.
      </li>
      <li>
        <dfn>Windows VST Path:</dfn> Clicking the <kbd class="menu">Edit</kbd> button
        pops up a dialog to manage the directories that will be searched for Windows
        VST plugins. When modified, Ardour will offer to scan those paths for plugins.
      </li>
      <li>
        <dfn>Path:</dfn> are the paths chosen above.
      </li>
    </ul>
  </li>
  <li>
    <dfn>VST 3</dfn>
    <ul>
          <li>
        <dfn>VST 3 Cache:</dfn> Same as above, for VST 3
      </li>
      <li>
        <dfn>VST 3 Blacklist:</dfn> Same as above, for VST 3
      </li>
      <li>
        <dfn>Additional VST3 Path:</dfn> The VST 3 specs clearly define where
        the host application should look for plugins. Although Ardour provides a
        way to search other directories for plugin, it is out of spec and not
        recommanded.
      </li>
      <li>
        <dfn>Conceal VST2 Plugin if matching LV3 exists</dfn> When 
        enabled, gives precedence to the VST3 (more up-to-date) version of
        a plugin over its VST2 version, if both exists.
      </li>
    </ul>
  </li>
</ul>

<h3 id="preferences-plugins-audio_unit">Audio Unit</h3>

<ul>
  <li>
    <dfn>Audio Unit</dfn>
    <ul>
      <li>
        <dfn>Scan for [new] AudioUnit Plugins on Application Start</dfn> When
        enabled, new AU plugins are searched, tested and added to the cache
        index on application start. When disabled, new plugins will only be
        available after triggering a 'Scan' manually.
      </li>
      <li>
        <dfn>AU Cache:</dfn> Clicking the <kbd class="menu">Clear</kbd> button
        removes all AU plugins from the list of plugins available to be
        inserted into the processor box. A new AU plugins scan is then required.
      </li>
      <li>
        <dfn>AU Blacklist:</dfn> Clicking the <kbd class="menu">Clear</kbd>
        button makes blacklisted AU plugins available to be added to the processor
        box.
      </li>
    </ul>
  </li>
</ul>

<h2 id="preferences-monitoring">Monitoring</h2>

<ul>
  <li>
    <dfn>Monitoring</dfn>
    <ul>
      <li>
        <dfn>Record monitoring handled by:</dfn> determines whether Ardour provides
        monitoring of incoming audio or whether monitoring is provided by hardware.
        See <a href="@@monitoring">Monitoring</a> for more information.
      </li>
      <li>
        <dfn>Auto Input does 'Talkback'</dfn> when enabled, the 
        <kbd class="option">Transport > Auto Input</kbd> option also sets
        the tracks to monitor its audio input when transport is not rolling.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Solo</dfn> contains settings that affect the use of
    <a href="@@muting-and-soloing">solo, muting</a>, and
    <a href="@@panning">panning</a>.
    <ul>
      <li>
        <dfn>Solo controls are Listen controls</dfn>: when enabled, the
          soloed track is soloed only on the monitor bus, the master fader mix
          is not affected by the solo. This option can also be set by enabling
          pre-fader listen or after-fader listen in the <strong>Mixer</strong>
          monitor section.
      </li>
      <li>
        <dfn>Exclusive solo</dfn> when enabled will only solo the last
          track selected for solo. Previously soloed tracks will be un-soloed.
          This setting is also available from the <strong>Mixer</strong> monitor
          section.
      </li>
      <li>
        <dfn>Show solo muting</dfn> when enabled outlines the mute
          button on tracks and busses when another track is soloed.
      </li>
      <li>
        <dfn>Soloing overrides muting</dfn> when enabled allows a track
          to be heard when it is soloed while muted. This setting is also
          available from the <strong>Mixer</strong> monitor section.
      </li>
      <li>
        <dfn>Solo-in-place mute cut (dB):</dfn> sets the attenuation of
          the other tracks when another track is soloed in place. This setting
          is also available from the <strong>Mixer</strong> monitor section. The
        default is "&minus;inf" for &minus;&infin;, meaning the other tracks are
        totally muted.
      </li>
      <li>
        <dfn>Listen Position:</dfn> determines what is listened to when
          the solo controls are used as listen controls. The options are
          after-fader or pre-fader.
      </li>
      <li>
        <dfn>PFL signals come from:</dfn> determines whether the
          pre-fader listen position is before or after the pre-fader processors.
      </li>
      <li>
        <dfn>AFL signals come from:</dfn> determines whether the
          after-fader listen position is before or after the after-fader
          processors.
      </li>
    </ul>
  </li>
</ul>

<h2 id="preferences-signal_flow">Signal Flow</h2>

<ul>
  <li>
    <dfn>Master</dfn> 
    <ul>
      <li>
        <dfn>Enable master-bus output gain control</dfn> adds a gain-stage to
        the master-bus and a Loudness Analyzer &amp; Normalizer button that
        calculates the Loudness (LUFS) of the session (or a range selection), 
        and normalizes the loudness according to various standards.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Default Track / Bus Muting Options</dfn> sets the muting options
    for a newly created tracks or bus. The mute options for an existing track
    or bus are changed by the right-click context menu on a mute button.
    <ul>
      <li>
        <dfn>Mute affects pre-fader sends</dfn> when enabled pre-fader
          sends will be muted by default.
      </li>
      <li>
          <dfn>Mute affects post-fader sends</dfn> when enabled post-fader
          sends will be muted by default.
      </li>
      <li>
          <dfn>Mute affects control outputs</dfn> when enabled control
          outputs are muted by default.
      </li>
      <li>
          <dfn>Mute affects main outputs</dfn> when enabled main outputs
          are muted by default.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Send Routing</dfn> affects <a href="@@aux-sends">aux and external sends</a>.
    <ul>
      <li>
        <dfn>Link panners of Aux and External Sends with main panner by default</dfn>
        when enabled, sends follow the channel panner. When disabled, sends can panned
        independently of the channel panner and fader. Double clicking the send in the
        processor box toggles the main panner and fader between the aux send and the
        channel.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Audio Regions</dfn>
    <ul>
          <li>
        <dfn>Replicate missing region channels</dfn>: if a track is N-channel,
        and the region has fewer channels, this option copies the existing
        channel's data for this non-existent one. If left unchecked, the missing
        channels will stay silent.
      </li>
        </ul>
  </li>
  <li>
    <dfn>Track and Bus Connections</dfn>
    <ul>
      <li>
        <dfn>Auto-connect main output (master or monitor) bus to physical ports</dfn>
        auto-connects the outputs to the first N physical ports. In a session without a
        <a href="@@monitor-section">monitor section</a>, the master-bus is
        connected to the system's playback ports, and if a monitor section exists,
        the monitor-bus' output are connected.
      </li>
      <li>
        <dfn>Connect track inputs:</dfn> allows to choose when a new track is
        created whether its inputs will be automatically connected to the physical
        inputs of the system or not (hence the user has to manually connect it).
      </li>
      <li>
        <dfn>Connect track and bus outputs:</dfn> allows to choose, for any new
        track or bus created, whether its output will automatically be connected
        to the master bus, directly to the physical outputs or to nothing (the
        user has to manually connect it).
      </li>
      <li>
        <dfn>Use 'Strict-I/O' for new tracks or busses</dfn> determines the default
        choice for the <a href="@@trackbus-signal-flow">signal flow</a> of a newly created track or bus.
        This can be overridden in the <a href="@@adding-tracks-busses-and-vcas">
        Add Track/Bus/VCA</a> dialog
      </li>
    </ul>
  </li>
</ul>

<h2 id="preferences-metronome">Metronome</h2>

<ul>
  <li>
    <dfn>Metronome</dfn> handles the way Ardour's metronome is played when
    enabled in the <a href="@@transport-bar">Transport Bar</a>.
    <ul>
      <li>
        <dfn>Emphasis on first beat</dfn> plays a different sound when the first
        beat is played (e.g. 1/4 in 4/4, 1/3 in 3/4,&hellip;). When unchecked, all
        the beats are indistinguishable.
      </li>
      <li>
        <dfn>Use built-in default sounds</dfn> when checked, uses Ardour's own
        sounds for the metronome click. Unchecking this allows to set some custom
        sounds below.
      </li>
      <li>
        <dfn>Audio file:</dfn> selects an audio file for the beats, in any
        <a href="@@supported-file-formats">format</a> Ardour supports.
      </li>
      <li>
        <dfn>Emphasis audio file:</dfn> in conjunction with
        <kbd class="option">Emphasis on first beat</kbd>, selects an audio file
        for the first beats of each bar.
      </li>
      <li>
        <dfn>Gain level:</dfn> allows the metronome's click sounds to be boosted
        or attenuated.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Options</dfn>
    <ul>
      <li>
        <dfn>Enable Metronome only while recording</dfn>: when enabled, the
        metronome will remain silent unless Ardour is recording.
      </li>
    </ul>
  </li>
</ul>


<h2 id="preferences-control_surfaces">Control Surfaces</h2>

<p>
  This tab contains settings for <a href="@@control-surfaces">control surfaces</a>.
</p>
<p>
  It lists all the Control Surface protocols Ardour knows. To enable a
  <dfn>Control Surface Protocol</dfn>, the <kbd class="option">Enable</kbd> checkbox
  next to its name should be ticked. Editing the settings related to this protocol
  can be done by double-clicking its name or clicking the <kbd class="menu">Show
  protocol settings</kbd> (only for Generic MIDI and Open Sound Control).
</p>

<h2 id="preferences-metering">Metering</h2>

<ul>
  <li>
    <dfn>Metering</dfn>
    <ul>
      <li>
        <dfn>Peak hold time:</dfn> allows the meter to keep displaying the highest
        signal level for a period of time before reverting to showing the actual
        instantaneous value (unless an even higher peak occurs). The longer this
        time is, the easier it is to spot peaks, at the expense of instantaneous
        accuracy.
      </li>
      <li>
        <dfn>DPM fall-off:</dfn> describes how fast the Digital Peak Meters can
        go from a high value to a lower one. Faster values are more accurate but
        less readable.
      </li>
      <li>
        <dfn>Meter line-up level; 0&nbsp;dBu:</dfn> chooses a standard for the
        conversion between dBFS (Full Scale) which represent the numeric signal
        level, and dBu which represents the analog signal level. This value is used
        to configure meter-marks and color knee-points, or set the reference levels
        for various meter-types.
      </li>
      <li>
        <dfn>IEC1/DIN Meter line-up level; 0&nbsp;dBu:</dfn> sets the reference
        level for the IEC1/DIN Meter
      </li>
      <li>
        <dfn>VU Meter standard:</dfn> selects which standard to use for the zero
        value of the vu-meters, i.e. the analog dBu value that will show as 0 on the
        VU-meter.
      </li>
      <li>
        <dfn>Peak indicator threshold [dBFS]:</dfn> at that value and over, the
        signal will make the peak meter to turn red, indicating a level too high.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Default Meter Types</dfn> sets the default meters when creating a session
    or track. These meters can be changed afterwards by
    <kbd class="mouse">right</kbd>-clicking a meter.
    <ul>
      <li>
        <dfn>Default Meter Type for Master Bus:</dfn> defines which kind of
        <a href="@@metering-in-ardour">meter</a> will be used when creating a new
        session (does not apply to the current session).
      </li>
      <li>
        <dfn>Default Meter Type for busses:</dfn> defines which kind of
        meter will be used when creating a new bus (applies to the bus created
        after changing the value).
      </li>
      <li>
        <dfn>Default Meter Type for tracks:</dfn> same as above, for tracks.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Region Analysis</dfn>
    <ul>
      <li>
        <dfn>Enable automatic analysis of audio</dfn> generates the transient
        values (used in e.g. the <a href="@@rhythm-ferret">Rhythm Ferret</a>)
        automatically. When unchecked, the transient values will be generated
        on demand.
      </li>  
    </ul>
  </li>
</ul>

<h2 id="preferences-performance">Performance</h2>

<ul>  
  <li>
    <dfn>DSP CPU Utilization</dfn>
    <ul>
      <li>
        <dfn>Signal processing uses:</dfn> sets how many cpu processors can be
          used to do signal processing. It can be set to use one up to all
          processors.
      </li>
    </ul>
  </li>
  <li>
    <dfn>CPU/FPU Denormals</dfn> are a specific type of very small numbers that
    can cause issues with CPU consumption when using some plugins in some
    circumstances. Ardour provides two methods of handling the issue.
    Trying different combinations of these settings may minimize CPU consumption.
    <ul>
      <li>
            <dfn>Use DC bias to protect against denormals</dfn> adds a small
            constant value to numbers to move the numbers away from zero.
          </li>
      <li>
                <dfn>Processor handling:</dfn>, if the computer's hardware
            supports it, offers two methods that can be used individually or
            combined. Flush to zero and denormals are zero.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Disk I/O Buffering</dfn> settings determine how many seconds of
    audio off of disk will be buffered in memory. Longer settings reduce
    the risk of buffer under-runs but consume more memory.
    <ul>
      <li>
            <dfn>Preset:</dfn> will automatically choose the values for the playback
        and recording buffer based on the chosen size of the session. The
        <strong>Custom</strong> option allows to manually select the buffers with
        the two sliders below.
      </li>
      <li>
            <dfn>Playback (seconds of buffering):</dfn> sets how many seconds of
        audio Ardour will buffer during playback.
      </li>
      <li>
             <dfn>Recording (seconds of buffering):</dfn> sets how many seconds of
         audio Ardour will buffer during recording.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Memory Usage</dfn>
    <ul>
      <li>
        <dfn>Waveform image cache (megabytes):</dfn> sets the maximum amount of ram that
        can be used to store the images representing the waveforms in the editor. Past
        this amount, the images will be regenerated when needed, which can significantly
        decrease the system's performance.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Automation</dfn>
    <ul>
      <li>
            <strong>Thinning factor</strong> ranges from 0 to 1000 with larger
            values sending fewer automation changes. Thinning is like lossy
            audio compression, removing data that is less likely to be noticed,
            although the more is removed, the more likely the loss will be noticed.
            The advantage to thinning is reduced CPU usage.
          </li>
      <li>
                <strong>Automation sampling interval</strong> ranges from 1 to
        1000&nbsp;ms. Determines how frequently the automation input is
        sampled. The shorter the interval the higher the accuracy but also
        the higher the CPU requirements.
      </li>
    </ul>
  </li>
  <li>
        <dfn>Automatables</dfn>
    <ul>
          <li>    
        <dfn>Limit automatable parameters per plugin</dfn>: as some plugins
        (synthesizers, &hellip;) have a lot of parameters, and those parameters
        can be automated by Ardour, checking this will limit the number of parameters
        that are listed as automatable, hence making the lists shorter and the GUI
        more responsive.
      </li>
    </ul>
  </li>
</ul>

<h2 id="preferences-video">Video</h2>

<ul>
  <li>
    <dfn>Video Server</dfn>
    <ul>
      <li>
        <dfn>Show Video Export Info before export</dfn> Shows a warning message
        when exporting a video about licensing and offers to open the
        <a href="@@workflow-amp-operations#export">export video</a> section of
        this manual.
      </li>
      <li>
        <dfn>Show Video Server Startup Dialog</dfn>: when using video inside Ardour,
        this video is accessed via Xjadeo from a source file through a Video Server.
        This options shows the server's startup dialog (useful for debugging a
        malfunctioning video).
      </li>
      <li>
        <dfn>Advanced Setup (remote video server)</dfn> can be used when the setup
        is more complex than opening a local file with Ardour. The tools used behind
        the scene by Ardour allow a lot of flexibility, so for a competent user,
        the options below are provided to access a distant file (i.e. on another
        machine). The default options for the two following fields ("http://localhost:1554"
        and "/") are suitable for local files.
      </li>
      <li>
        <dfn>Video Server URL:</dfn> Base URL of the video server delivering the video
        through the network (<code>http://IP-or-address:port</code>).
      </li>
      <li>
        <dfn>Video folder</dfn> is the server's local path to the document-root,
        i.e. the files that can be delivered by the server.
      </li>
    </ul>
  </li>
  <li>
    <dfn>Video Monitor</dfn>
    <ul>
      <li>
        <dfn>Custom Path to Video Monitor (xjadeo) - leave empty for default:</dfn>
        Ardour bundles offer xjadeo bundled, so it should run flawlessly. Though,
        for custom builds or if a newer version of xjadeo is available, one can
        specify a path to the wanted version of xjadeo.
      </li>
    </ul>
  </li>
</ul>