Semitones help please.

[Dunks]

No its software, Actually it doesn't have to be 100 it can go from 0>1 this is what I have so far and sounds ok to me but to someone with a trained ear it may sound off:

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c   0
c*  0.8.33
d   0.16.67
d*  0.25
e   0.33.33
f   0.41.67
f*  0.50
g   0.58.33
g*  0.66.67
a   0.75
a*  0.83.33
b   0.91.67
c   1

Should I change this to 'Decimal value in 12-TET' Thats on the wiki site?

Weather a bit shitty down err.

[jonnyG]

Me again

A couple of thoughts... If you superimpose the above intervals on a linear slider the first few semitones will be bunched at the left-hand end of the scale and then progressively spread out. It's a logarithm thing. Also (bear in mind I haven't a clue what's going on here) you may need some separate fine tuning control. Or not.

[Dunks]

Me again

A couple of thoughts... If you superimpose the above intervals on a linear slider the first few semitones will be bunched at the left-hand end of the scale and then progressively spread out. It's a logarithm thing. Also (bear in mind I haven't a clue what's going on here) you may need some separate fine tuning control. Or not.

Thats what my problem was logarithm cheers.

[jonnyG]

No its software, Actually it doesn't have to be 100 it can go from 0>1

x1 - x2 makes more logic to my addled brain. That way the 1.000, 1.059, 1.122... thing could have been implemented directly. I'm still confused tho, your numbers are evenly spaced. Do they directly control playback speed?

Should I change this to 'Decimal value in 12-TET' Thats on the wiki site?

I imagine most people wouldn't know an equal temperament scale if it bit 'em on the arse. Suggest "semitones".

Weather a bit shitty down err.

Gah! Devon!

[Dunks]

x1 - x2 makes more logic to my addled brain. That way the 1.000, 1.059, 1.122... thing could have been implemented directly. I'm still confused tho, your numbers are evenly spaced. Do they directly control playback speed?

Yes they do 0 = normal speed, 0.5 = + half as fast and 1 = twice as fast. I could implement 1.000, 1.059, 1.122... directly just change 1 for a 0 as the number before doesn't really matter its just the distances between the notes need to be right.

[Meffy]

No its software, Actually it doesn't have to be 100

Then go with 0-96. Eight (logarithmic) steps per semitone, and you hit exact semitones along the way. Easy. Or if you must have 101 steps, make the topmost steps of the control, from 96 to 100, all return 96.

[Dunks]

I have sorted it now. I would love to use 96 or a multiple of 12 but for what I was doing I needed to go from 0>1, 1>2 .5>0 and .5>1 map 1 octave of a keyboard to a pitch slider. Thanks for the help though I now have a much better understanding of semitones.

[mr]

I believe it is better to talk about Hertz and not notes.
Find a table of Hz of all the notes of your octave and then do the math.

[jancivil]

No its software, Actually it doesn't have to be 100 it can go from 0>1 this is what I have so far and sounds ok to me but to someone with a trained ear it may sound off:

c 0
c* 0.8.33
d 0.16.67
d* 0.25
e 0.33.33
f 0.41.67
f* 0.50
g 0.58.33
g* 0.66.67
a 0.75
a* 0.83.33
b 0.91.67
c 1

Should I change this to 'Decimal value in 12-TET' Thats on the wiki site?

Weather a bit shitty down err.

I thought there were 100 steps, which complicated my thinking something awful on this.
Does it just jump from one s.t. to the next? you called it a slider, which had me thinking of a more continuous whatever. my addled brain was trying to take into consideration x amt. of steps in between the obvious ones here.

which would give you (88/12 =) 7 1/3 steps in between each s.t., which is impossible without some real 'scrambling and skewing'

weather pretty crap out here on the left coast too

[jancivil]

I believe it is better to talk about Hertz and not notes.
Find a table of Hz of all the notes of your octave and then do the math.

if the first frequency is given, I imagine his program will take care of that, these are demonstrably equal 'semitone' relationships acc'ding to decimal system.

[Dunks]

I believe it is better to talk about Hertz and not notes.
Find a table of Hz of all the notes of your octave and then do the math.

I tried this before asking here on KVR and I got very similar numbers to 1.000, 1.059, 1.122...but they went 0.000, 0.059, 0.122...which tells me the numbers 1.000, 1.059, 1.122... are the correct ones to use I can use these to go from 0>1 without having to do any maths.

[jancivil]

I think the difference between the two sets of numbers illustrates the difference between a linear scale and a logarithmic one, but I don't know.

to wit: the 'f#' is exactly HALF WAY to the octave from your tonic. *6/12ths*

in your maths, you have that result, .5, for 'f#' is situated half way between zero and one.

the other thing has 1.414214 for f#, and the closest thing to '1.5' is the 'g' or p 5th.

now, I've never had a real math class, and I can't get my brain around 1.4 for a tritone to tonic relationship, it isn't linear.

I'm extremely curious, now: My first instinct tells me that in terms of speeding up a motor, what you got from dividing 1 by 12, straight linear, would do the job.

Is this not correct?

[Dunks]

I'm extremely curious, now: My first instinct tells me that in terms of speeding up a motor, what you got from dividing 1 by 12, straight linear, would do the job.

Is this not correct?

This is what I am confused about. I thought there had to be 12 value equal distance from each other like it says on Wiki, so dividing 1 by 12 would give the 12 equal distances between notes, straight linear. By using 0.000, 0.059, 0.122 they seem bunched up at the bottom end of the scale.

[Dunks]

The slider is straight linear, so wouldn't the numbers also need to be straight linear?

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0  = 0 
.25 = 1/4 
.50 = 1/2
.75 = 3/4
1   = 100% pitch increase

[jancivil]

yes, if the slider is in fact linear, and if the logarithm-derived numbers appear skewed on it it must be, then I believe you've already got it sussed.