manual/include/aux-sends.html

<p>
  <dfn>Auxilliary sends</dfn> are <a
  href="/working-with-plugins/processor-box/">processors</a> in a bus or
  track channel strip. They tap the signal at a specific point in the signal
  flow (pre-fader, post-fader, before or after EQs and other plugins, etc.)
  and send a copy of that signal somewhere else, without affecting the
  normal signal flow downwards to the channel fader.
</p>
<p>
  Usually, aux sends from several tracks are collectively sent to a
  dedicated <dfn>Aux bus</dfn> in Ardour, to create a monitor mix for a
  musician, or to feed an effect unit. The output of such a bus might
  be routed to separate hardware outputs (in the case of headphone or monitor
  wedge mixes), or returned to the main mix (in the case of an effect).<br
  />
  Aux sends are not JACK ports, with <a href="@@external-sends">
  External Sends</a> Jack ports are created so it is also possible to
  send the tapped signal somewhere else directly, which is not usually
  possible on hardware mixers.
</p>

<p>
  It may be useful to
  <a href="@@comparing-aux-sends-and-subgroups">compare and contrast</a>
  the use of aux sends with <a href="@@subgrouping">subgrouping</a>.
</p>

<h2>Adding a new aux bus</h2>
<p>
  Choose <kbd class="menu">Session &gt; Add New Track or Bus</kbd>. In the
  <kbd class="menu">New Track &amp; Bus</kbd> dialog, select "Busses" in the Track/Bus
  selector at the upper right.
</p>

<h2>Adding a send to an aux bus</h2>
<p>
  Context-click on the processor box for the track you want to send to the bus, and
  choose <kbd class="menu">New Aux Send</kbd>. From the submenu, choose the bus you
  want to send to. A send will be added (and will be visible in the processor box).
  Note that the submenu may be empty if you have not created a bus yet.
</p>

<h3>Pre-fader and Post-fader Aux Sends</h3>
<p>
  Depending on whether you context-click above or below the fader in the processor box,
  the new aux send can be placed before or after the fader in the channel strip.
  <dfn>Post-fader</dfn> aux sends are typically used when using an aux for shared signal
  processing (FX), so that the amount of effect is always proportional to
  the main mix fader. <dfn>Pre-fader</dfn> sends ensure that the level sent to the bus
  is controlled <em>only</em> by the send, not the main fader&mdash;this is typical
  when constructing headphone and monitor wedge mixes.
</p>

<h2>Adding a new aux bus and sending a Track Group to it</h2>
<p>
  You can add aux sends to all members of a group and connect them to a new aux bus
  with a single click. After creating the track group (and adding tracks to it),
  context-click on the group tab and choose either
  <kbd class="menu">Add New Aux Bus (pre-fader)</kbd> or
  <kbd class="menu">Add New Aux Bus (post-fader)</kbd>. A new aux bus will be created,
  and a new aux send added to every member of the track group that connects to
  this  aux bus.
</p>

<h2>Altering Send Levels</h2>
<p>
  You can alter the amount of the signal received by a send that it delivers to the bus
  it connects to. There are three approaches to this:
</p>
<h3>Use the Send Fader</h3>
<p>
  Every send processor has a small horizontal fader that can be adjusted in the usual way. It is
  not very big and so this can be a little unsatisfactory if you want very fine control
  over the send level.
</p>
<h3>Mapping the Main Fader</h3>
<p>
  Double-clicking on the send in the processor box will allow you to use the
  big fader of the mixer strip to control the send. The visual appearance of
  the mixer strip will change to reflect this. Double-click the send again to
  revert back to normal function for the strip.
</p>
<h3>Map Aux Sends To Main Faders</h3>
<p>
  Pressing the button marked <kbd class="menu">Aux Sends</kbd> on a aux bus will
  alter the channel strip for every track or bus that feeds the aux bus. Many
  aspects of the strip will become insensitive and/or change their visual
  appearance. More importantly, the main fader of the affected channel strips
  will now control the send level and <strong>not</strong> the track gain.
  This gives a larger, more configurable control to alter the level. Click the
  <kbd class="menu">Aux Sends</kbd> button of the aux bus again to revert the
  channel strips to their normal use.
</p>
<h2>Disabling Sends</h2>
<p>
  Clicking on the small "LED" in the send display in the processor box of the
  channel strip will enable/disable the send. When disabled, only silence will
  be delivered to the aux bus by this track. When enabled, the signal arriving
  at the send will be delivered to the aux bus.
</p>
<h2>Send Panning</h2>
<p>
  Send panners can be configured to either be independent of the main
  panner, or to follow it. The latter could be useful for Reverb effects, or
  for in-ear monitor mixes delivered in stereo.
</p>