T.R | Title | User | Personal Name | Date | Lines |
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2203.1 | under vms: $ bas scale then $ lin scale $ run scale | VIKING::JANZEN | Tom FXO-01/28 228-5421 MSI ECL Test | Wed Dec 13 1989 14:01 | 24 |
| DECLARE REAL CONSTANT LOWC = 16.3516, A440 = 440.0
DECLARE INTEGER CONSTANT NOTESPEROCTAVE = 12, TopnoteinOctave=11,TopOctave=7
DECLARE REAL PITCH
DECLARE REAL TemperedScale(0 TO TopOctave, 0 TO TopNoteInOctave)
DECLARE STRING NoteNames(0 TO TopNoteInOctave)
RESTORE
FOR Pitch = 0 to TopNoteInOctave
READ NoteNames(Pitch)
Next Pitch
FOR Octave = 0 TO TopOctave STEP 1
FOR Pitch = 0 TO NotesPerOctave-1 STEP 1
TemperedScale(TopOctave,Pitch)=LOWC*2**(((Octave*NotesPerOctave)+Pitch)/12)
print "MIDI: ";Octave*NotesPerOctave + Pitch + 12;
PRINT "Pitch: ";NoteNames(Pitch);Octave;
print "Frequency: ";temperedscale(topoctave,pitch)
NEXT Pitch
NEXT Octave
DATA "C ", "C#", "D ", "D#", "E ", "F ", "F#", "G ", "G#", "A ", "A#", "B "
END PROGRAM 1
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2203.2 | Good start, What's it all mean??? | WOOF::DRIGIAN | | Wed Dec 13 1989 14:13 | 5 |
| Slick, I'll convert this into C (the language not the note) so I
can use it with other programs.
Bryon
|
2203.4 | An Octave is A Dollar After Inflation? | DRUMS::FEHSKENS | | Thu Dec 14 1989 08:51 | 20 |
| A little background that may make the algorithm more than just
something to translate:
What you'll get is an "even tempered" scale, which is what just
about everybody uses today. There are other scales, but that's
a whole 'nother discussion.
An even tempered scale divides the octave into 12 equal steps.
As the ear/brain perceives pitch based on ratios of frequencies,
this means that each successive note's frequency is the same multiple
of the previous note's frequency. Since there are 12 notes in the
octave, there are 12 successive multiples, so we get r^12 = 2, or
r = 2^(1/12). The 12th root of two is about 1.06...
Real pitchweenies talk about "cents". A cent is 1/100 of a half
step, or 1/1200 of an octave, i.e., the 1200th root of 2. Cents
are useful for talking about small pitch differences.
len.
|
2203.5 | I cents understanding | WOOF::DRIGIAN | | Thu Dec 14 1989 09:15 | 1 |
| This is beginning to make cents!
|
2203.6 | | TOCATA::PICKETT | David - Beware of the dogma. | Thu Dec 14 1989 16:23 | 4 |
| 34 Cents. Is that the standard 'Stretch' as in stertched octaves in
piano tuning? If so, I'll experiment with my ESQ-1
dp
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2203.7 | -23 to +34 across the 88 | DDIF::EIRIKUR | The best of tines, the worst of tines | Thu Dec 14 1989 17:27 | 16 |
| Looking at the tuning chart for my Yamaha CP60M, which may be a bit different
from a "normal" piano (if there is such a thing), I see that the highest note
is to be tuned 35 cents sharp, and the lowest note 23 cents flat. This is
obviously what stretch tuning is all about.
Having now tuned the beast, I can say that this doesn't seem to be unnatural.
It sounds right tuned this way, and when tuned dead-on, the extremes of the
keyboard beat against the middle octaves. I will have to look up an
explanation for this effect.
Eirikur
Roland is touting the stretch-tuning modes on their new Rhodes pianos. I
wonder if this is really a relevant feature. I somehow suspect that they don't
produce "inharmonic" samples, which is *why* one would need to stretch-tune.
Maybe they do have special samples....
|
2203.8 | perfectly in tune=frigid | MILKWY::JANZEN | Tom FXO-01/28 228-5421 MSI ECL Test | Fri Dec 15 1989 10:06 | 11 |
| Each piano is different. You can't tune j-random piano to a frequency
counter to math some other j-random piano. It won't be right.
It might work on electric pianos because their physics is simpler, I
suspect.
In the old scientific american article the physics of the piano I seem
to recall that the 43rd harmonic of a piano tone was a perferct fourth
high, roughly. That's around 5+ octaves. However, such a high
harmonic is very hard to hear. Lower harmonics, being louder, probably
produce the beats we hear as normal piano sound, a kind of "warmth"
when not excessive.
Tom
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