View Full Version : Need Help--Changing Tempo w/o Changing Pitch


Chris Long
June 29th, 2004, 07:00 AM
Hi All

I need to replace a 120 second section of a soundtrack. The music is an excerpt of a solo piano piece by Satie. I can't get a copyright clearance on the recording I was using, and the film is cut to it--the editing is finished, I'm hapy with it. I can get a friend to record the piece (it's public domain; I'll use my PDX-10). Unfortunately, she can't quite play it well at the tempo I need.

So, I need to record her playing it and then speed the passage up to fit the already edited film. Problem is, I want to keep it in the same key. I know I can do this a few different ways--but I need advice about how you might do it, or how you think it would come out the best, quality-wise. I know that there can be quality problems when you mess with a file in this way. Fortunately, I don't think I have to speed it up TOO much--just enough to make it fit.

I have Premiere Pro, Sonar 1 and Cool Edit Pro, all of which can do this in some measure, I believe.

Any other/better softwares that are GREAT at this? What approach or application will give me the best quality?

Thanks in advance for your ideas!
Chris

Rich Frankel
June 29th, 2004, 07:19 AM
The slickest way to get around this is to have her play it on a midi capable instrument into a sequencer, then just speed up the midi track... for flawless playback.

If you must speed up the audio, you will get some artifacts, its just the state of the tech.

but I say, midi keyboad into a sequencer, that's the sneaky way to do it.

;)

good luck.

Chris Long
June 29th, 2004, 07:40 AM
That's a great approach--one which I hadn't thought about at all. I wish I could do it, I don't a have midi keyboard that would be decent enough to use, and I couldn't get my performer to use it (I'm guessing here, but I bet I'm right). She's doing a big favor recording this, and we're doing it in her home on her grand piano so she'll be comfortable. I think I'd spook her with unfamiliar equipment...

A great idea, though...

Matt Stahley
June 29th, 2004, 02:40 PM
Any decent software sampler or loop based music production software would be what i would use. On the PC I guess that would be Acid and or Fruityloops possibly the samplers in Reason.These usually have the time strecth features you are looking for and would probably yield the best results as far as maintaining pitch with tempo changes. There could be some freeware out there that would do this too. Im a mac user so I dont pay much attention on the PC freeware out there on the net.

Peter Jefferson
July 5th, 2004, 03:41 AM
soundofrge has a time stretch picth shift function whereby yu can retain the pitch while adjsuting length (Vegas has thing built in with virtually no external processing required)

a good audio tool which is becomig the new ProTools is Ableton Live.. very VERY powerful workstation utility... prolly the biggest balls out there..

Douglas Spotted Eagle
July 5th, 2004, 08:59 AM
While I'd absolutely, unequivocably dispute that Ableton "has the biggest balls" it is a good app. But it won't change tempo well without shifting pitch.
Sound Forge is good for this, ACID ROCKS at this, and now Vegas, but only Vegas 5 does this really well. It's all in the resample, something the SOFO/Sony boys have always done.
Fruityloops is quite good too, and Sonar 1 will do a good job if you don't need to go beyond about 12% of tempo change. In fact, most tools can do a decent 5% or so. Past 10%, I'd use ACID or Vegas 5.
Or buy a tool called Timeshift. It's about 100.00, and is excellent, but no better than ACID 4 or Vegas 5.

Cris Linscott
July 6th, 2004, 03:02 AM
I've no experience of Ableton but, echoing Douglas's comments, I rate Acid for these duties; Sonar I find a bit more complicated but maybe thats more to do with my familiarity than anything else - have used it most recently to couple an acapella vocal with an acoustic guitar where both performances had been made without a pitch reference.
This looks interesting too http://www.celemony.com/melodyne/index.html

Chris Long
July 12th, 2004, 07:11 AM
Thanks all. I'm in the process of doinbg it right now, and the results are mixed with tht epps I've tried so far. Cool edit Pro does it, but so far the quality isn't what I'd like. Same with Premiere--works fine, stays on pitch, just becomes fuzzier and more "remote" sounding. Not whaty I'd like, as I said.

I'll try to test it out in Acid, see how that works.

Thanks again!