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Hey, I'm curious to what exactly pitch-shift and pitch-correction is. And what's the difference. I'm trying to put an effect in my song that at the end of every four lines, I want my vocals to get really deep, almost like you slowed a record down, but I want it to keep the same timing. How can I do that? Thanks! God Bless! :D

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IIRs Wed, 11/30/2005 - 03:03

Pitch shift allows you to change the pitch of a sound without changing its speed ;) its quite a serious process though, and the quality of the results will vary wildly depending on the algo and settings you use.

Pitch correction is "intelligent" pitch shifting that will detect the pitch of a note, work out whether its in tune or not, and then apply corrective pitch shift if needed.. Antares Autotune is the original one, usually used to make bad singers sound less toe-curling :roll:

anonymous Wed, 11/30/2005 - 06:22

IIRs wrote: Pitch shift allows you to change the pitch of a sound without changing its speed ;) its quite a serious process though, and the quality of the results will vary wildly depending on the algo and settings you use.

Pitch correction is "intelligent" pitch shifting that will detect the pitch of a note, work out whether its in tune or not, and then apply corrective pitch shift if needed.. Antares Autotune is the original one, usually used to make bad singers sound less toe-curling :roll:

so in pitch-correction, you say it's "intelligent"... how does it find which note to move the singer to. Do you have to play the melody on a piano or something to have something to compare it too?

IIRs Wed, 11/30/2005 - 07:41

Depending on the software you may be able to quantise the pitch to the nearest equal tempered semitone, to the nearest note in a pre-defined scale, or to the last MIDI note-on it recieved.. or you may have the option to view the pitch of the performance plotted against time on a graph which you can then edit.

Better to spend the money on singing lessons if you ask me.. ;)

Calgary Wed, 11/30/2005 - 21:05

"Pitch shifting" is when you alter the pitch of a tone without affecting the speed. For example when you create a harmony vocal part by cutting and pasting a chunk of the main vocal and then transposing it, lets say upward by a third (4 semitones) and instead of the vocal sample getting shorter as you increase the frequency, your software compensates and "expands" the length of the new sample in time to meet the original timeline, i.e. your transposed vocal part is still perfectly in time with your song even though the fundamental frequency is now much higher. I'm not expert but that's my understanding of what "pitch shifting" is commonly referred to as.

Pitch correction is somewhat related. Or at least that's my understanding. The pitch correctors I've seen worked in the same way as harmonizers or tuners in that they are either chromatic or tempered to a key which you select. So if you set it to "C Major" let's say, then it uses the frequencies for C, D, E, F, G, A, and B as the target zones, as pitches deviate from those values the machine attempts to "round them off" as best it can to the "most appropriate" neighboring note as per it's logic system and your threshold/level settings. I'm not saying that's how they all work but some do. The net result is that if you have a perfect guitar solo except for one bent note which is a tiny bit flat you can use a tool like autotune to save yourself an hour of re-tracking the part. At it's worst these tools are employed in an attempt to compensate for poor musicianship.

If you really want to hear what autotune can do just listen to any of the zillion or so "albums" by people like Ashlee Simpson, Brooke Hogan, Kelly Osbourne, etc. I'd wager that there probably isn't a single tune on those albums which wasn't touched in some way by some form of pitch manipulation. As far as I know no truly skilled musicians ever use Autotune, jazzers laugh at the very notion. 8-)

Reggie Thu, 12/01/2005 - 13:32

I heard that was an old studio trick of Geddy Lee.

But seriously, how did they do the voices for The Chipmunks in the days before digital processors? It would have had to have been a speed thing, right? Maybe I will go bust out the Chipmunks Christmas album and slow it down to see what the dudes singing really sound like.
:lol:

Kev Thu, 12/01/2005 - 18:25

possibly with tape speed tricks
slow the tape for record and then speed up for playback

you still get to pitch against the rest of the track during an overdub
end result is much like using a pitch shifter

the Helium idea means your voice is different as it leaves your mouth and you would need to learn to control your new voice

it was just an interesting idea

anonymous Fri, 12/09/2005 - 20:50

The Chipmunks was almost certainly vari-speeded.

Unless they did use helium. You should try nitrous oxide, then you really will have trouble controlling your "new voice"...

How about recording someone using helium/nitro/whatever, tracking to a song at high speed, then slow it down to normal speed to see if they got it right? I might try that myself.

Calgary Fri, 12/09/2005 - 21:16

All they did was slow tape to half speed and then speak/sing at half speed. This results in a one octave transposition which is perfectly in time when played back at normal speed. It's very easy to do, just slow down your favorite tune to half speed and sing along with it in real time, then bring it back up to normal speed and you'll sound exactly like they did. 8-)

You can do it with any instrument too. It's actually a neat trick for getting an extra octave out of an electric guitar. (y)