Currently Being ModeratedMay 3, 2012 1:22 PM (in response to Keith Barkley)
You can use the AUPitch effect on all your tracks to alter the pitch. You'll have to do some math:
E.g., if you want to play the piano with a 432 Hz tuning, you'll have to set the AUPitch (which goes in cents = 1/100 of a semitone) to minus 31 cents.
)Here's the math: one cent up is (2^(1/12))^0.01 = 1,00058 times the frequency. Divide the frequency by the same number to go one cent down. How many cents is it to go from 440 to 432 Hertz?
1,00058^x = 440/432 = 1,01851
x*log1,00058 = log1,01851
x = log1,01851/log 1,00058 = 31,63)
Currently Being ModeratedMay 3, 2012 3:59 PM (in response to Christoph Drösser)
Christoph, this is very interesting.While I am mathematically challenged,I am eager to learn.
I can divide 444 by 432 to get 1,0181 (though I dont know what the ^ means).
after that I cannot yet replicate the 31,63.
I divided 1,01851 by 100058 but that does not give me the same answer(1,01796)
also what does log mean?
Currently Being ModeratedMay 3, 2012 4:08 PM (in response to nandi)
^ means to raise to a power, 3^2 is 3 squared, or 3*3.
log means the common base 10 logarithm function.
If you don't have a scientific calculator, google can do it for you.
but just use the -31 cents and you don't need to know the math.
Currently Being ModeratedMay 7, 2012 2:31 AM (in response to nandi)
I admit it's a bit hard to comprehend because frequencies don't go linear but exponentially - each octave doubles the frequency of a tone. So to go up one semitone (in an equal tuning), you have to multiply a frequency by the 12th root of 2 (or divide by this factor to go down one semitone). One cent is 1/100 of a semitone, so it's the 1200th root of 2. The calculation computes the number of cents you need to adjust from a 440 Hz to a 432 Hz tuning.
Currently Being ModeratedMay 7, 2012 5:10 AM (in response to Christoph Drösser)
I guess I should have listend more in high school math class some 40 years ago...
When I have time I will follow the advice here and try to learn how to arrive at various hertz.
For now, I have started recording in GB at -31 cents.
Currently Being ModeratedJun 6, 2012 9:06 AM (in response to nandi)
I have tried to use AUPitch to set each track (or also the Master track insted) to -31 cent.
But GarageBand (latest Version) insists to reset it to -24 cent! (after reopening the AUPitch)
Any ideas why od how to change this?
Currently Being ModeratedJun 8, 2012 9:23 AM (in response to OrpheusXL)
Ha! Found the mistake in GB!
The input into the AUPitch plugin is not being accepted, as long as the "Music keyboard" (Musik-Tastatur in German) is opend and visible. Closing it, everything works as it should, even with -31 cent.
Good, that we talked about it!