is a parameter curve?
Parameter curves are a fast and accurate
way to change the sound of an instrument while
music is playing.
As you may have read in previous chapters,
general digital effect settings, in the "Play
tools" palette, let you
change the global volume of a document, as well as
apply a bass boost,
These settings apply to all the
instruments in the document. If you change the
volume, for example, it
affects the whole piece.
Then on each staff, digital effect
processors can be inserted in order to add
Flanger, Chorus, Reverb, etc. These are "Effect
Starting in Harmony Assistant version 8.0
(Melody Assistant 6.0), several curves can be
related to each staff.
curve defines the way a parameter evolves during
time. You can use both
curves and effect processors on the same
staff. If they conflict,
the parameter curves will take priority over the
A curve lets you control the variation of a
parameter more precisely
than an effect processor does.
You can set the parameter value exactly for each
time position in the
music, or you can make the parameter
vary smoothly between two time positions.
Here are some samples of use:
Varying volume while a note is played
Fading out of a piece
Performing a complex bend (frequency variation)
Sending specific commands to a MIDI
A parameter curve can operate under two different
- Discontinuous values: the parameter will take
the required value, and keep it until a new
value is encountered
- Continuous valuers: the parameter will take
the required value, and evolve continuously to
the next value, taking all the values inbetween.
How do I add a curve?
We have seen that in scroll mode (the only
display mode available in Melody Assistant) or in
page mode with
handles enabled (Harmony Assistant only), little
icons are displayed at
the left of the staff. The fourth icon from the
is a green arrow.
Clicking this icon opens a pop-up menu. You can
select the curve to be
edited. While a curve is being edited, the staff
is grayed out to make
the various parameter curves easier to see and
The first menu item resets the standard
display and editing mode for notes on the staff.
The next one allows you edit note
velocities (power). A red curve joins the
notes. The higher the
point on the curve, the larger the value for note
velocity. By clicking
in "Editing" (pencil)
mode, you can change the velocity value of each
Then, with Harmony Assistant only,
you can adjust the delay and pressure time
for each note. A
line shows the delay (offset from the note head)
and the pressure time
(line length). Just as for velocity, you can can
change these values
in "Editing" (pencil) mode.
A second section in the menu grants
you the access to other parameters, like volume,
You can also define parameters that
are related to MIDI output management.
In contrast to velocity, delay and pressure time,
parameters in this second section are not related
individual notes, but to the staff itself.
Deleting or moving a note
won't change the
curve for a parameter in this section. It is
therefore preferable to
adjust the curves after having input all the
When a curve exists for a parameter,
the curve name is displayed in bold in the pop-up
The third section of the menu allows you to configure
the curves, or to apply changes to
How do I edit a curve?
A curve is made of segments
(colored lines) between control handles
(little squares). On
left side of the staff, the minimum and maximum
value of the parameter
as well as its name. You can configure the
parameter's curve to change
its minimum and maximum value, as well as its
To add a control handle, click the
staff in "Editing" (pencil) mode.
To move a control handle, drag it
in "Editing" (pencil) or "Select" (lasso) mode.
To move a curve, drag its first
control handle while holding down the Shift key.
To change several values at a time,
include the group of control handles to change in
the selection range,
then drag one of those control handles.
To split a curve into two parts,
click a segment with the delete tool (lightning
To delete a control handle, click
it with the delete tool (lightning bolt)
To delete a curve completely or
partially, select the range to be deleted, then
You can copy/paste parts of a curve on the same
staff, or from one
parameter to another.
You can add or subtract a value
to a selected range using the apply option
the pop-up menu.
You can fill the selection range
(or the whole staff if nothing is selected) with a
triangle or square
curve using the apply option in the
How are the
Values of parameters that are displayed
as a curve are applied in real-time while the
music is playing, 200
second. The value is read at the required time
position in the written
score, and adjusted to produce smooth changes
between each pair of
control handles. If there is no segment at a given
position (which can
occur if you split a curve by deleting a segment,
for example), the
is not applied.
Some parameters are specific to digital
output, others to Midi only, and some to both
digital and Midi output.
The array below shows each possible
parameter curve as well as its field of action.
||from 0 (quiet) to 100 (loud)
||Right - left panning position
||from -100 (extreme left) to 100
||Pitch variation (pitch bend)
||from -2400 (-2 octaves) to 2400
||from 0 (no effect) to 100 (maximum
||from 0 (no reverb) to 100 (maximum
||Resonator (filter) resonance
||from 0 to 100
||Resonator cutoff frequency
||from 50 Hz to 4000 Hz
||from 0 to 100
||Distortion color (bass/treble)
||from 0 (bass) to 100 (bright)
||from 0 (regular) to 100 (treble)
||from 0 (regular) to 100 (bass)
|MIDI-specific from a to f
||User-defined MIDI command
||from 0 to 16383 (14-bit MIDI parameter
If you define your parameter curve
to be applied to all staves in the document, it
will be applied to
staff, EXCEPT staves in which a separate curve
also exists for this
This lets you define global curves
for an entire song, which are overridden by
specific curves in some
portions of some staves. For best readability, it
is recommended (but
not required) to attach all global
curves to the first staff of the document.
These parameters are specific to
your MIDI device and let you control the
non-standard features of your
You can define up to 5 MIDI parameter
curves in each staff.
parameters are specific to your
synthesizer, they can have
on other hardware devices.
To define this kind of parameter,
open the parameter setting window and select the
parameter in the list.
Then enter command text that describes what is to
be sent to your
The manual provided with your MIDI hardware should
Command input is made in hexadecimal
(base-16 digits, each digit being a value between
0..9 or a letter
A..F). The value
read on the curve will be used to replace
sequences of the characters
'm' and 'l' in your command line: 'l' is replaced
by the least
significant bits (LSB) of the curve value, and 'm'
is replaced by the
most significant bits (MSB), as explained in the
table below. The 'n'
character will be replaced by the MIDI channel
All other characters, such as spaces
or commas, are ignored and can be used as
Number of bits
Let's take an example:
In my Roland JV-30 synthesizer manual,
I read that a specific command, part of the NRPN
section, can be used to manage the internal filter
for this command can be in the range from 0 to
I open the setup dialog from
the curve pop-up menu, and select the first MIDI
parameter curve. I
the minimum (0) and maximum (127) values. Since I
need the range 0-127,
using 7 bits, the value from my curve will
therefore be represented
in the command text by 'll'.
I enter the command text "Bn 63
01 Bn 62 20 Bn 06 ll" (referring to my synthesizer
manual for the
details of the command). Now I simply have to draw
shape to send internal filter cutoff frequency
commands to my
synthesizer. The character 'n' will be replaced
by the channel number used for that staff, and
'll' by the value that
has been read from my
Harmony-Melody does not check
of the MIDI command string.
You are therefore
responsible for ensuring that it
matches the description in your