Altering or Creating Scales
A list of some scales are available
under Options | Scale - the
other built-in scales are for different periods of western music. But
this list can be tailored to your needs, and Options | Scale
Pitches & Menu launches the dialog for creating scales, or
altering or deleting ones already on your list. The dialog allows you
to adjust the notes of the
scale relative to SA. The pitches of the current scale are displayed in
relationship to the notes of equal temperament (up to 50 cents plus or
minus). If you just want to define a scale according to the
actual sounding of the notes, for instance to define it by an existing
tuning on a keyboard instrument or on another fixed-pitch instrument
like the santoor, or from the sympathetic strings, first be
sure your pitch is set
accurately to SA. Start the Tuning Graph if it isn't running.
(You may launch the Pitch
& Range dialog to set SA even when the Scale dialog is
active). After SA is centered,
adjust the appropriate slider
[1] for each of the other notes as they are
played. The tuning graph will change as you do so; you just stop when
the pitch of the note being tested is drawn on the center line, neither
sharp nor flat. Of course you will want to expand the lower graph by
raising the splitter bar, and perhaps show it at a greater
magnification [select View | Lower
Graph Scaling], so that it can be read in finer detail.
If you want to enter specific pitch values for a
particular scale, they must be calculated in the form of cents, and
then set accordingly. You can type the cents deviation from Equal Temperament into the edit boxes
[2]. Or, if you know the values as a
decimal ratio, enter that into the Cents
Convertor below
[3], and the cents value will be displayed for
you. For people working with just intervals such as theorists
often give for various ragas - type the numerator
and denominator into the ratio control
[4] and the cents value will be
calculated and displayed, and a decimal ratio shown as well. This value
will show you the offset from equal temperament. Here is an example:
the pure ratio 5/4 is 386.3 cents, which comes closest to the equal
temperament note of 400. So it is the 4th note in the list, and its
offset is minus 13.7 cents. You can see this value in the natural
scale
[5], or also in the Western meantone temperament, as they both use an
exact major third.
By checking the Auto-adjust Note Value
[6]
box you can have the appropriate note adjusted automatically, after you
enter a valid decimal or integer ratio. Only values between 1 and 2
will have an effect. [But, be careful when entering subsequent integer
ratios in Auto-adjust mode - if you enter the numerator and it makes a
value between 1 and 2 with the denominator value already in its edit
box (or vice versa), a note may get changed that you did not intend.
You may need to delete one of the fields first. Or, uncheck the box.]
An Undo
control is provided
[7], which will restore previous values one note at a
time.
You can enter or edit the name associated with this
scale. OK allows tuning to
continue with any changes you have made, but no alteration is made to
the stored scale list. Those changes will be lost if the program is
closed or another scale is selected. Use Save to permanently record any
changes you made to a scale (including changing the name), Save As to
enter the information as a totally new entry in the scale list, and Delete to remove the selected scale
from the list. (After Deleting a scale from the list, its values
continue to be used for tuning until you decide to select a new one.
And so in the case where you decide your deletion was a mistake, you
can restart the Scale Pitches dialog and Save the
deleted scale As a new name,
then rename it).
Here are the ratios that were
used in creating the "Natural Scale".
re 16/15
Re 9/8
ga 6/5
Ga 5/4
Ma 4/3
ma 45/32
Pa 3/2
dha 8/5
Dha 5/3
ni 9/5
Ni 15/8
There are
instances where you may wish to compare
the scale to another than equal temperament, and so the comparison
scale
[1] can be selected from the
drop-down list of scales (the dialog always begins with Equal as the
comparison). For instance, it is claimed that some ragas have notes
with a lower-than-usual pitch [ati-komal];
so by listing the offsets relative to
the basic raga scale which has been called Natural Scale, you can
immediately set or see how much the flatter notes have been altered.
Look at the image to the left. Here we wish to generate a new scale
with an extra flat komal Re
[R1]. Some theorists fix that note as 256/243, and we have entered that
value in the right-hand fields in the Cents
Convertor section
[2], which has given us the corresponding decimal
value for 256/243, An Undo
control is provided
[7], which will restore previous values one note at a
time. An Undo
control is provided
[7], which will restore previous values one note at a
time.
1.05350
[3], and 90.2 as the cents value
[4], which it also displays as the
offset from re [dark green] in equal temperament, -9.8. We have
selected Natural Scale, with which we began, as the reference scale
[1], to
show how the scale is identical except for the one note we have
changed; we can see how much flatter it is than the standard re, -21.4
cents
[5].
The main tuning graph will reflect this change, as the lines for re
(dashed dark green) will move downwards somewhat. The Undo button
[6] now shows the color and name of the most recently changed semitone, re. And a name for
this new scale has been entered in the Scale
Name field
[7] at the top; consequently the Delete button has been
grayed out, as we can delete only the originally selected scale from
the list, and the Save As...
button is activated for creating a new
entry in the list of scales.
After you have built up a selection of scales that
are useful to you, you may wish to reduce menu clutter by deleting
those sample scales from the original list that you don't want.
The scale list is maintained on a file which you
should back up periodically. Back up both the scale and instrument
files, TMScales.dta and TMInstruments.dta, together, as they are linked. If
that file is not found or is corrupt,
Tuning Meister has a built-in Natural Scale which it will use.