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Author Octave overlap in uTune?
kindredlost
 I found the solution. See the last lines. I wrote to you on the blog page but thought I'd take your advice there and write here as well... I have a pentatonic octave scale that I like to use with midi from a standard keyboard. When playing the scale the point at which the next octave begins is doubled. In other words lets say the ROOT is note value 61 and the octave is note value 66 five key presses above the root. The NEXT note played on the keyboard which is a single semitone above the octave is reading 67 on the uTune display but is exactly the same voltage as the previous 66 value, so each octave has a one-note duplicate key before proceeding on through the scale. The same effect occurs traveling lower on the keyboard. Here is another way to explain it... C#3 = midi 61 (ROOT) D3 = 62 D#3 = 63 E3 = 64 F3 = 65 F#3 = 66 (OCTAVE) G3 = 67 (OCTAVE AGAIN) This is where the voltage output stays the same as the previous note so I get the same OCTAVE note on my VCO. Each subsequent note up the keyboard follows the scale map fine but are shifted down by one note value voltage. This makes a nice symmetry for playing. Every other octave (two octaves up form the original root) is exactly the same on the keyboard but I am also using the uTune module with midi tuning software to my other midi to c/v modules so there is a tracking problem. They output the scale correctly and I get a progressive offset across the octaves. Is there a parameter to edit which can smooth out this duplicate note overlap? Also I notice this does not happen if I choose to use a scale with 12 tones or more. I haven't tried other variations of less than 12 notes yet, just 5 notes. Here is a truncated description of the scale I am loading into uTune if anyone wishes to duplicate it... NAME: 5 EDO, Sulendro 13113 (note count) N:006 01 : 1/1 02 : 9/8 03 : 4/3 04 : 3/2 05 : 16/9 R : 2/1 a very simple Javanese scale. EDIT: I found the cause of my problem. I have too many entries in the table. I dropped out the 1/1 on the first entry and everything is fine. Learning as I go here.
tubbutec
 Happy you found the answer, for completeness I am including my answer I already sent you via mail: Hi. The reason for this is the way you defined the scale. The unison 1/1 for note 1 is always implicit. So by defining it again you created this double note. Have a look at other scales, the initial 1/1 is always missing. This is how scales are defined in scala. So your scale should be Note count: 5 (it is pentatonic after all) 01: 9/8 02: 4/3 03: 3/2 04: 16/9 R: 2/1
tubbutec
I can already see the next question coming from someone else:

 Quote: But what if I want a scale without the 1/1 entry?

Well there are two solutions to this. One involves math, the other makes use of a feature unique to µTune.

The µTune solution
µTune can deactivate certain notes in a scale. (In the scale editor this is the small arrow next to the note number). If you want to deactivate the root, just deactivate the repeating interval (2/1).
If you try to play a deactivated note, µTune will pick the nearest active note and play that instead.
Deactivated notes will be saved with the scale, and scale files are still compatible with the scala format. By the time of writing however the deactivation is ignored by other systems.

The math solution
This has actually nothing to do with µTune, but applies to all Scala compatible devices.

First of all it is important to understand how a scale is constructed in scala. There is always some base note (1/1) and all other intervals are defined relative to this note. So the entry 9/8 means: 9/8 * 1/1.
As you can see, it is not only unnecessary to include the 1/1 entry, changing it would also be meaningless as it is just a reference for all other intervals.

The scale is repeated with a certain interval, which is the last entry of the scale. In µTune this entry is marked with R, the repeating interval. In this case it it 2/1, an octave. So if all notes of the scale are used, the next notes will be 2/1*1/1, 2/1*9/8, and so on.

So if you want a scale, that does not include its root you must chose a new root. In the example above this would be 9/8. Now you divide all notes by 9/8 so the relations by all intervals are maintained.

00: (9/8) / (9/8) = 1/1
01: (4/3) / (9/8) = 32/27
02: (3/2) / (9/8) = 4/3
03: (16/9) / (9/8) = 128 / 81

Our new scale thus becomes:

01: 32/27
02: 4/3
03: 128/81
R: 2/1