manual/include/subgrouping.html

<p>
  <dfn>Subgrouping</dfn> (sometimes known as "Grouping" or "Audio Grouping")
  is a way to collect related signals together to apply some common
  treatment, before sending them on to the main mix. One standard
  application is to group several tracks belonging to the same instrument or
  section (such as a drum kit or horn section), to be able to adjust their
  volume with a single fader, after their inner balance has been set using
  the track faders.
</p>

<p class="note">Ardour also provides <a href="@@control-masters-mixer-strips">VCAs</a>
  that is a very flexible way to adjust the volume of a group of tracks/busses when
  no additionnal processing is needed.
</p>

<p>
  Create a subgroup from an existing Track/Bus group is done by <kbd
  class="mouse">right</kbd>-clicking on the relevant <a
  href="@@the-track-and-bus-group-list">group tab</a>, and choosing <kbd
  class="menu">Add new subgroup bus</kbd>. A new bus will be created and every
  member of the track group will have its outputs disconnected from other
  destinations and then connected to the new bus inputs. The bus outputs will
  feed the master bus unless manual connections have been selected in the
  session preferences. The bus will be named after the track group name.
</p>
<p>
  Alternatively, a group can be created manually, by first adding a new bus,
  then, for each track to be fed in the subgroup bus, disconnecting its outputs
  from the master and connecting it to the inputs of the subgroup bus instead.
  This can be done in the global audio patchbay or on a track by track basis via the
  output button of each track's channel strip.
</p>
<p>
  Remove a subgroup (bus) is done by <kbd class="mouse">right </kbd>-clicking on
  the track group tab, and selecting <kbd class="menu">Remove subgroup
  bus</kbd>. Simply deleting the bus itself will <strong>not</strong> restore
  signal routing to the way it was before the addition of the subgroup
  bus&mdash;tracks that had been subgrouped will be left with their main outputs
  disconnected.
</p>