Pitch correction: Cents vs. overall percentage?

[gyrofrog.com]

I have obtained a concert recording which, I'm told, is 32 cents sharp. My editing software (Audacity & Sound Studio, on Mac OS X) allows me to change pitch in terms of a percentage, but not cents (which IIRC is hundredths of a semitone).

Is there an easy way to calculate the change in percentage that would equate to changing the pitch so it's 32 cents flat? Or could the difference be attributed to variously encoding/decoding the audio at 48kHz or 44.1kHz somewhere in the lineage?

Thanks in advance.

[joel hamilton]

I have had times when something was "concert pitch" A= 442 and had to work with that all throughout overdubs, due to an, um, "error" or "oversight" by the producer of the song... Anyway: I really just wound up piyching the global tuning of pitchdoctor until it sounded good to me, and i am very critical about pitch when i need to be.

I dont know the specific stuff you are using well enough, nor do I consider myself good at math

Try moving the percentages around until the track sounds good to you. It helped me to have the pitch correction on full tilt while getting the pitch right.

[gyrofrog.com]

I dont know the specific stuff you are using well enough, nor do I consider myself good at math

Try moving the percentages around until the track sounds good to you. It helped me to have the pitch correction on full tilt while getting the pitch right.

To complicate matters futher, aren't cents relative to the pitch in question? E.g., the difference in Hertz between A1 and A#1 is different then between F3 and F#3.

If there isn't an easy way to do this, then I will probably just do this by ear (or set a tuner in front of the speakers) if I mess with it at all.

Thanx!

[joel hamilton]

I dont know the specific stuff you are using well enough, nor do I consider myself good at math

Try moving the percentages around until the track sounds good to you. It helped me to have the pitch correction on full tilt while getting the pitch right.

To complicate matters futher, aren't cents relative to the pitch in question? E.g., the difference in Hertz between A1 and A#1 is different then between F3 and F#3.

If there isn't an easy way to do this, then I will probably just do this by ear (or set a tuner in front of the speakers) if I mess with it at all.

Thanx!

You could also move a signal generator plugin around until it sounds really good (again, at A 440...up to 442, then 441, then 445 whatever) and see what sounds best. then put the pitch correction plug AFTER the signal generator and get it to "center" on the pitch you know is coming through it. Seems like it would take some of the guesswork out of the deal if you can work with a fixed frequency rather than an evr changing melodic line... Just a suggestion...

Hope that helps at all.

[digdug]

Isn't it just 100 cents per half step? I don't know what you meant by percentage change. What's 100% change in your scenario here? An octave? A half-step?

[digdug]

To complicate matters futher, aren't cents relative to the pitch in question? E.g., the difference in Hertz between A1 and A#1 is different then between F3 and F#3.

I'm pretty sure that's not the case with even tempered scales - like the western 12tone scale.

[gyrofrog.com]

Isn't it just 100 cents per half step? I don't know what you meant by percentage change. What's 100% change in your scenario here? An octave? A half-step?

Percentage of what? That's a good question! I'm in Sound Studio now. looking under the "Filter" menu. I select "Pitch and Tempo..." and theres a field where I can set the percentage (default=100). When I change it to 50% the track time doubles. So it's a percentage of the "playback speed," which is what I had assumed to begin with.

So the question is how to convert playback speed, as a percentage, into hundredths of a semitone.

[gyrofrog.com]

Hypothesis:
Lowering pitch by 1200 cents results in a pitch change of one octave. Reducing tape speed by 100% also results in a pitch change of one octave. So, using 7th grade arithmetic (i.e. 32/1200 = n/100, alternatively 100/1200 = n/32), in order to reduce the pitch by 32 cents, or 32/1200ths, I need to change pitch by 2.6666...% or 2.6666..../100ths.

Assuming I have this right, this is not enough of a difference to be due to a discrepancy in 48kHz vs. 44.1kHz encodings/decodings. But I will probably just try reducing pitch by 2.666% and leaving it at that.