Envelope tracks are a powerful utility in EnergyXT’s sequencer component to automate
variables within a composition over time.
Whether it is automating track volume, the frequency cutoff for a synthesiser part
or even the sequencer tempo, the envelope track gives a simple and graphical means
of programming changes into a composition that will be reflected in a final render
to audio.
Envelope tracks can only be edited in-line within the sequencer component. This
means that all editing is done within the sequencer interface. Other track-types
allow the opening of a more comprehensive window for editing.
To add an envelope track to an arrangement, right-click within the track header
and select Add->Envelope.
Once the envelope track is added (and selected), hitting H will either minimise
the track or return to normal track height. Double-clicking the track header will
open the envelope track for editing.
A right-click on the track header of the envelope track will reveal all the standard
track options as used by other track types. However, the Output option is worth
further explanation here.
For an envelope track output, there are more options available than for other track
types. It is possible to output to another component added to the sequencer via
the main mixer and to redirect to one of the sequencer’s MIDI Out ports. It is also
possible to direct envelope output to an Audio Track. This is, so far, parallel
with the MIDI Track output options.
However, for the envelope track it is also possible to output to other MIDI Tracks.
It is useful to be able to tie a MIDI Track’s automation to the track itself and
the automation will be passed through automatically to that track’s output including
any midi plug-ins that may exist on that track.
It is also possible to direct an envelope to the sequencer tempo. This allows complete
automation of a composition’s tempo at any time not only by switching tempos but
also by controlling acceleration and deceleration of tempo.
Additionally, within the Sequencer Mixer (toggled via F9) the same options are available
as in a MIDI Track: MIDI Channel and track delay options, including the ability
to insert midi effects in the chain.
Within the Envelope Track header are the key configuration options for the envelope
track itself:
Mute/Solo buttons are available to control the activation and deactivation of the
Envelope Track in relation to other tracks within the arrangement.
The Envelope Track has a title which can be altered via the right-click context-sensitive
menu.
A CC field exists to align the envelope with a selected MIDI change controller.
This is used to map the envelope automation with a given parameter in the target
component.
A Resolution drop-down selector is used to select between MIDI resolution and high
resolution for the automation envelope. The difference between these two resolutions
are as follows:
- MIDI res - operates within the MIDI standard which means that the values that
can be passed via automation are constrained to a total of 128 different steps/levels
(0 – 127) so would be considered a fairly low resolution of automation.
- High res - uses the 32 bit capabilities of the VST standard to allow much finer
variations over time. When using High resolution, the CC value is still used for
mapping purposes. However, the automation is converted to 32 bit VST automation.
The Value field is used to display the value of a given node within an automation
envelope. The field is editable allowing the fine adjustment of any selected node.
The Line option allows for the toggling between two automation drawing types:
- Ramp/Curve - used for gradual changes in value over time.
- Step/Flat - used for immediate changes in value at given points.
The Envelope Track itself consists of a grid where the vertical grid lines are aligned
with the snap value in the sequencer – which also controls the snap value when adding
a node to an envelope. The track is also divided into 4 quadrants vertically as
a guide when adding or moving nodes.
Each node is shown by a small square which can be click-dragged to a new location
(horizontally and vertically) or right-clicked for deletion. A value is shown at
each node which represents where between 0.00 and 1.00 the node is placed.
Clicking on a node will select the node and its associated “segment”. In the case
that the segment is of type Ramp/Curve, there will be a control point shown by a
small circle which is used as a control for defining the shape of the curve within
the segment. Click-dragging will alter the definition of the curve for the selected
segment.