looking for advice on time stretching an acapella

hi, i am looking for some advice with the following project i cant get my head around ..

 

i have a track, 85bpm and also have the acapella i have played along with the original track to check they both match .. so i assume the bpm of the acapella is also 85bpm?!

 

what i want is to use this in a project with a tempo of 128. now if i time stretch this to 128 it goes all chipmunk style, how can i get this to work ??

 

any advice would be brilliant, i have searched the internet looking for some tips and thought this site would be the best place to ask for help ..

 

thanks in advance

Does anybody have any ideas how I can achieve this?? I know it's possible because I've heard a few dance remixes of the track at 128bpm. Someone said half the tempo so that would be 64bpm. Would going from 85 to 64 bpm be to much of a decrease? I don't want to alter the pitch of the acapella

Logic has Flex audio though I have Melodyne and use it for just this sort of thing. Melodyne has very little in the way artifacts

And the interface is very good. I highly recommend Melodyne if you can afford it.

Try using flex in polyphonic mode and shrink the acapella to suit the new tempo.

I've done it a million times as remixer, and I can tell you that it will be very difficult to get satisfactory results without a lot of manual work. 85BPM to 128BPM is a huge stretch. 20-25% is about the limit of decent timestretching and you're trying to go about twice that. Melodyne, flexpitch and other algorithms can handle the main stretch for you, but you will have a lot of unwanted artifacts and odd sounding vibrato. Sometimes it helps to stretch down to half-time before stretching up to the ultimate tempo. So in your case go from 85 to 64, then 64 to 128. It doesn't always give better results but it can.

 

Then once you have a stretched vocal,chop it up so that all the weird artifacts and vibratos (mostly at the ends of phrases) can be removed. Then replace those parts will the corresponding parts from the original vocal and crossfade the regions until they sound good. You will be going word by word and syllable by syllable through the vocal. It is extremely tedious and time consuming work but it is really the only way to get a good vocal when the tempo difference is that great.

thanks for your advice here guys! i didnt expect it to be quite so simple ! lol if only there was a magic button..

 

lots of reverb on the acapella too, mainly through the right of the stereo spectrum which creates even more artefacts

 

the acapella i am playing with is "kosheen - hide u" ... would you think half time and then doing as you say with chopping unwanted parts out ? if i sped the acapella to 128 would this not speed her voice up to some kind of 'chipmunk' style ?

 

thanks for your time ! interesting to see how others work

If you are working with the original track - the tempo is 170BPM.

The staccato nature of the vocals will work in your favor because there is less vibrato and pitch variation.

 

I would always go to Melodyne first, but that's just a personal preference. Give it a try just using Flex Time in Logic to do the stretch for you. I would start in monophonic, but you can experiment with the algorithms. Try stretching down from 170 to 128 vs. up from 85 to 128. It can also help to stretch the vocal in smaller bits - like 4 bars at a time instead of trying to stretch the entire file in one go. Then take a listen and use tricks like splicing in bits and pieces from the original, or chopping up words and nudging them on the timeline a bit. Every vocal is a different challenge and you just have to experiment to see what works.

 

The Creamer and K remix is at 134BPM so that should give you a good idea of how your final product should sound.

 

As for the reverb if it is mainly on the right side, then you can get rid of it using mid/side processing.

If you are working with the original track - the tempo is 170BPM.

 

Which is the original? The full band vid I looked at is hanging out at around 137 bpm......

http://www.youtube.com/watch?v=Yzwx4VvykNg

 

OTOH, the acapella, also on iTunes, is at 170 (maybe that's what you meant?). And it sounds very natural so I'm wondering if she recorded it at two different tempos.

 

As for the reverb if it is mainly on the right side, then you can get rid of it using mid/side processing.

Listening to the iTunes preview of the acapella version and shutting off my right channel completely eliminates the FX so this is easy to get rid of.

 

Put the file on a stereo audio track and then, from the stereo / mono selector at the bottom of the track, select the left side only and then do a Bounce In Place to get an FX-free file.

 

I was curious what kind of stretching I could get out of this so I recorded the preview into Logic 9 (set to 170 bpm). Then I flexed it using the monophonic setting and changed the tempo to 128 and it sounds pretty good!