OpenMPT tunings (was: OpenMPT suggestion: well temperament)

[LPChip]

I think the S2x command (for IT) could be used as a tuning switcher, since the docs say it's only there "for MOD compatibility"... i.e., useless as far as I can tell. If for some reason you actually need to use that effect, you wouldn't be using alternative tunings anyway, so it'd be a no-op in OpenMPT with no alternative tunings defined, which makes it exactly the same as before, right?

That'd give you 16 tunings, 0-F, to switch to on the fly, which would probably be plenty. If you want more, you're probably a microtonalist...

Yes it might be reasonable to have such modcommand available; using S2x might be easy, but since the tuning things are not currently intended to be included in IT(nor XM), it shouldn't be too difficult to add even new command for this. But anyway, this, or the "tuning override" are not on the top of todo's right now; there is more than enough objective get even a simple version 'out' first.

Makes me wondering though... Why on earth would you ever want to switch between tunings during the song? that will probably screw up your song? Maybe its better to affect the pitch instead? Eg. S28 = middle, higher number and the pitch is slightly raised, lower and its slightly lowered? I think that will be better to adjust in case you want that for one note.

[SoundCrafter]

Makes me wondering though... Why on earth would you ever want to switch between tunings during the song? that will probably screw up your song? Maybe its better to affect the pitch instead? Eg. S28 = middle, higher number and the pitch is slightly raised, lower and its slightly lowered? I think that will be better to adjust in case you want that for one note.

Actually, I too thought about usinf SFx.  You might want to switch, well like furrykef said, if you were going to use chord with the same instrument. But for compatiblilty purposes, it might be best just to make two of the same instruments with different tuning.

[LPChip]

I can understand that you want a different temperament for your song, but for each instrument sounda likes stupid?

They can collide in such way that it becomes hard to use them at the same time?

[furrykef]

Yes it might be reasonable to have such modcommand available; using S2x might be easy, but since the tuning things are not currently intended to be included in IT(nor XM), it shouldn't be too difficult to add even new command for this.

Well, A-Z are already taken for effect names, but I guess it would be possible to use 0-9 as well.

Makes me wondering though... Why on earth would you ever want to switch between tunings during the song? that will probably screw up your song?

If you're using just intonation, you will need to retune to use certain chords. For example, if you're tuned to C, you cannot use a full D chord (either major or minor) because the fifth is a wolf interval -- it will go "WOWOWOWOWOW", like a bad chorus effect, which is almost always undesirable. So you would want to switch to D tuning for that chord.

You might also want to use just intonation for most of a song, but, for example, you have a bit you recorded on an electric guitar, so that part needs to be in equal temperament to be in tune with the guitar.

Put both of those reasons together and you might have three tunings in your song right there.

Maybe its better to affect the pitch instead? Eg. S28 = middle, higher number and the pitch is slightly raised, lower and its slightly lowered? I think that will be better to adjust in case you want that for one note.

I don't think I really like this idea. How do you know how much to adjust pitch? And it wouldn't be a good substitute for being able to switch tunings, because each one of those you use means you can't use another effect in its place, whereas my idea would affect the entire song, and so only one channel would have to deal with that.

I can understand that you want a different temperament for your song, but for each instrument sounda likes stupid?

They can collide in such way that it becomes hard to use them at the same time?

I agree on this point. You'd almost never want to use more than one tuning concurrently.

- Kef

[LPChip]

To reply on the above post...

I don't know exactly how it works, but it looks to me that an entire song is played with the same scale? Eg: you play in a C maj, then a A min, eg. You want to change how that sounds right? Not just a C maj?

But maybe what I'm saying here isn't possible? The first time I've came to this fact IRL is yesterday. and before that only by reading the posts.

[furrykef]

I don't know exactly how it works, but it looks to me that an entire song is played with the same scale?

Well, for one thing, you would use a different scale when you do a keychange, such as playing in C major and transposing up to D major. In some tuning systems, such as well temperament and (obviously) equal temperament, this is not a problem, but in just intonation, it is. But with just intonation, you may need to retune even if you stick to the same scale (using "scale" in the sense of a series of notes like C D E F G A B).

You can write a song completely in C major and still need different tunings if you use just intonation... I know that sounds kind of odd, and really, it is, but it's the way it works. In the C major scale, we have these intervals (those not necessary for this example are omitted):

• C = 1:1
  
• D = 9:8
  
• E = 5:4
  
• F = 4:3
  
• G = 3:2
  
• A = 5:3

If you play C-E-G, it will sound good. From C to E is 5:4, and from C to G is 3:2, both of which, due to the small integers, are obviously consonant intervals. Let's also calculate the interval from E to G. To do this, we multiply them together, with one ratio having the bigger number on top and the other having the bigger number on the bottom: 5:4 * 2:3 = 5:6 (which we can also write as 6:5 in the context of intervals), another small ratio. So C major is a nice, clean chord all the way through, which is not surprising for a C major scale.

Now let's look at a D minor chord: D-F-A. D minor is a chord in the C major scale, since D, F, and A are all in the scale, so one would expect to be able to use it. First let's look at D to F: 9:8 * 3:4 = 27:32 (or 32:27). This sounds decent; it's flat, but it's tolerable. And from D to A is 9:8 * 3:5 = 27:40 (or 40:27), which is way too flat and sounds like a honky tonk piano without the charm (if you're using a piano sample ). That's a "wolf interval": it howls like a wolf. The only good news is that F to A is 4:3 * 3:5 = 4/5 (or 5/4), a nice, clean interval, but that doesn't make the wolf interval sound any better. You have three options: play D-F and omit the A; play F-A and omit the D; or temporarily retune to the D major scale.

This also shows why just intonation pianos are not popular...

- Kef

[LPChip]

I see, but I think its better to make a new command instead of using S2x, because Sxy is used to alter a sound, instead of being a global effect. It will become confusing that way.

But the programmers can deal with that.

Basically you want to assign what key you are playing in right?

So ?13 can mean:

? = the letter, char for the command)
1 = the note: 0=C, 1 = C# etc. (like appregio effect, taken from a C)
3 = the kind of chord: 0 = maj, 1 = min, 2 mj7 etc...

And based on that, the right tonation will be used?

[furrykef]

That's a good point about Sxy being used to alter a channel, not the song. I do think a new effect altogether would be a better idea.

I think it would be most useful if there were a numbered table of tunings the user can define. #0 might be equal temperament, #1 might be well temperament, #2 might be a just intonation C scale. It's somewhat unlikely that a user would use a wide variety of tunings in a single composition -- but not inconceivable for a very long piece -- but I don't think it'd be less convenient than the alternatives. Whether you need two tunings or a dozen, it will work for you.

Perhaps we could define ?0x as a set of presets built into MPT: ?00 would be equal temperament, ?01 through ?0C would be just intonation in C through B major, ?0D through ?0F would be reserved, and ?10 through ?ff would be the user-defined tunings. I don't like starting with C major on ?01 instead of ?00, but then, neither do I like assigning the default value, equal temperament, to something other than ?00. Perhaps ?FF for equal temperament wouldn't be a bad choice, though.

I'm renaming the thread now, since we've gone beyond the scope of well temperament...

- Kef

[LPChip]

I'd rather use standard settings for where possible?

Since a tonation scale would only go from 0 to B, you can use C to F which are 4 numbers to set speciffic commands? Cus each number has 16 slots.

Eg: ?Cy sets tonation to y
and so fort?

[furrykef]

I'm not sure I understand what you mean.

[speed-goddamn-focus]

I think it's smoother to use different instruments. perhaps a system where cloned instruments could inherit chosen attributes of another, so that if you change the "parent" the children could change too? Honestly, isn't that a terrific idea?

[furrykef]

I think it's smoother to use different instruments.

Could you explain your reasoning?

[speed-goddamn-focus]

I think it's smoother to use different instruments.

Could you explain your reasoning?

Choosing an aptly named instrument is easier than remembering which number goes with what tuning.

[furrykef]

Yes, until you have to change to "Piano - D scale", "Bass - D scale", "Pad - D scale", and "Trumpet - D scale" for a D chord, just to switch back to "Piano - C scale", "Bass - C scale", "Pad - C scale", and "Trumpet - C scale" again on the next chord -- compared to doing just two commands.

It'd also be annoying having all those essentially duplicated instruments. If you have sixteen instruments in two tunings each, suddenly you have 32 of 'em!

You do have a point, but is using instruments the solution?

- Kef

[LPChip]

Since using 2 tonations at a time will probably cause trouble anyway, I think its best to change it for the entire song, and therefor not make it instrument dependend but song dependend.

As for using your own scales, you could use F as a changer, like SFx also was ment for the changer. C,D and E can be used for anything if required.

Cus if you have like 7 different tonations, you can easilly use 16-7 = 9 custom ones. Or if more is desired, you can use entirelly C D and E which each has 16 values to use custom presets.

Note that each custom preset can have a diagram for each note with each chord in it.

Eg: if we decide that 0 = C, 1 = C# etc... and 0 = maj, 1 = min, 2 = maj7, 3 = maj7 etc.

you can make your own scheme, then simply do:

?F8 (select your custom set)
?01 = C maj
?53 = F maj7

You can even make it easy on the programming this way:

you store the values in a table, where the x axis is the note and the Y axis is the chord. Then you read out the value, and refer to the table where in ?xy, the x goes through the x axis, and the y goes through the y axis.

Eg:

Code Select Expand

     |C |C#|D |D#|E |F |F#|G |G#|A |A#|B |
------+--+--+--+--+--+--+--+--+--+--+--+--+
C     |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
CM7   |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
C7    |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
Cm    |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
Cm7   |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
Cdim  |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
Cm7   |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
Caug  |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
Csus4 |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
C7sus4|??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
C6    |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+
Cm6   |??|??|??|??|??|??|??|??|??|??|??|??|
------+--+--+--+--+--+--+--+--+--+--+--+--+

Copied this from the manual of my Roland FP-2