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View Full Version : Pitch correction


Five
2005-01-10, 12:58 AM
I've never done pitch correction, so I thought I'd fish for some advice here. I've got a show that runs way too fast. My concept was to do a hell of a lot of trial and error and match the tuning of several discrete notes in different places in the show to find the correct adjustment. I'll be using CEP. Anyone who has some experience with this please chip in with a few tips for ol' Five.

h_vargas
2005-01-10, 02:34 PM
i've done that procedure about a dozen times or so, using CEP/Audition, with excellent results. your approach sounds fine, i think. when i've done it, i always tried to find a good recording of band 'X' from the same tour (preferably a show with a date close to the one you're editing). this helps a good bit for side-by-side listening comparison.

oh, here's two tips that i think are quite useful:

1) while doing the trial and error for adjusting the tempo/pitch, only select a small portion of audio (approximately 1 - 2 minutes is good). it's just a time saver, really, as you obviously don't want to spend the time/CPU processing on an entire show before you find the "magic number" to adjust it by,.

2) use the Highest Quality setting in CEP's "Time/Pitch" correction, and use the "Resample - Preserves neither tempo nor pitch" option. from all of the tapes i've listened to that played way too fast or way too slow, when you simply try to adjust *only* the pitch or *only* the tempo, the result doesn't sound good/natural. when you use the "Resample" option in CEP's Time/Pitch plugin, the result is much more natural-sounding. besides, it's common sense that when a tape/recording is sped up, the pitch goes up a la Alvin and the Chipmunks, and vice versa... so wouldn't the process of fixing the problem be to essentially "slow the tape down" (if it plays too fast) in a way such that the pitch shifts accordingly as well?

a lot of trial and error is what it does come down to. as i said, i've done this type of processing several times. hope this info is of some help.

Five
2005-01-10, 03:15 PM
thanks, I knew there had to be somebody with experience to give me a couple pointers.

So my next question is... what's the best way to tell when you've found the "magic number"?

h_vargas
2005-01-12, 04:34 AM
welcome. hopefully at least something out of my last post will turn out to be useful for you.

the "magic number" again goes by a lot of trial and error. if you want to get very "technical" about it, if you locate a good recording of close proximity (i.e. date) to the one you're working on, i believe you can use Cool Edit's "find beat" function. (it's likely called something else, but i can't think of it off the top of my head right now.) then, compare the appropriate beats in the "normal playing recording" with the beats CE locates for the same portion in the fast/slow playing recording.

my less scientific method for this is just listening repeatedly to a correct-playing part of the same song from a nearby dated recording over and over. after multiple listenings to the same intro/part of a correct-playing show, the beat sort of melds its way into your head. then, you can more quickly find the 'magic number' for the incorrectly-playing recording.

also, if you have a decent set of ears (which i'm sure you do :D ), then you should be able to narrow down the possibilites quickly by listening to the singer's voice and the guitars... the pitch really is a big help in finding that "right sound."

Five
2005-01-12, 10:43 AM
ahh, yes! this is very helpful, thanks very much :D