Changing the tempo of an audio file?

[VirusTI]

Changing the tempo of an audio file in Logic Pro 9 using the Time and Pitch machine seems pretty shit, makes the audio glitchy / stutter in some places, yet in Traktor for example, you can change the tempo of whatever's playing, even drastically and it sounds perfect? Am I doing something wrong? /derp

[bassinine]

i know in ableton it does the same thing, unless you change the clip setting from "normal" to "complex pro."

i'm sure logic has an option to change how it stretches it. can get paulstretch and do it also if you can't figure it out.

[press]

flex time, or option drag the bottom edge.

[jam1]

'Time Stretch Regions to Locators' in the audio tab at the top of the arrange window will stretch any selected piece of audio to the loop markers. I use this all the time for percussion loops and it sounds fine most of the time. Can sound weird with pads and vocals.

edit: You can stretch by 400% of the original file.

[VirusTI]

'Time Stretch Regions to Locators' in the audio tab at the top of the arrange window will stretch any selected piece of audio to the loop markers. I use this all the time for percussion loops and it sounds fine most of the time. Can sound weird with pads and vocals.

edit: You can stretch by 400% of the original file.

Done that mate, still doesn't sound great. I just don't see how Traktor etc can do it so smoothly and yet programs designed to do that are so crappy /derp

[invisibled]

sorry mate but im going to have to side with everybody else. I use logic for everything and mainly use flex time by option dragging the lower edge. If it's a full acapella i'll use the time and pitch machine and choose the advanced/complex algorithm. I have gotten bad results before but just tried another option and got a good result.

[wormcode]

Well they use different core time stretching algorithms. Native Instruments along with most other companies (Steinberg, Ableton, Image Line and loads more) use the Elastique algorithms from Zplane, whereas Logic and only a couple of others like I think Sonar use Radius from iZotope as the main algorithm. That would account for differences, but how much I'm not sure. You might wanna give Reaper a go since I think it's got the most time stretching options of them. Either way you'll have the most success by chopping it into smaller sections and working with those.

[bassinine]

http://hypermammut.sourceforge.net/paulstretch/

best stretching software around, plenty of different algorithms to choose from.