Slow down audio without shifting pitch

[supercluster]

Hello,

I'm looking for a piece of software that allows one to slow down audio without distorting the pitch... I know i've seen this in the past but I'm having a hard time rediscovering it. Does anyone have any suggestions?

Thank you

[Zarith]

This is called "Time Stretching". Most audio softwares have this feature. It's nothing exceptional.

A short list:

Vegas
Cubase
Wavelab
Logic
Acid
Pro-Tools
Reaper
Sonar
Digital Performer
Samplitude

[pflosi]

ableton live

[Villi]

Here's a recent thread about time stretching: http://www.vintagesynth.com/forum/viewt ... =3&t=53528

[Z]

Before time stretching was available, I'd run slowed down (or sped up) samples through a pitch shifter. I used a Korg DVP-1 back then.

[Solderman]

There are also different algorithms used by different apps. Ableton Live 8 uses élastique Pro(by ZPlane) for its Complex Pro warp mode, and élastique efficient for the other warp modes. Reaper offers both élastique Pro and Dirac LE. Serato has its own algorithm called "Pitch 'n' Time", but it is absolutely dreadful for slowdown stretch. I'm told the Dirac algorithm in Wavelab is the best of that bunch, but it really just depends on what material is being stretched, how much time you need to stretch it by, and how fast your CPU is, if you need real-time(non-destructive) processing.

A bad algorithm will usually just sound glitchy, most obviously in the transients of drums.(Kicks and Snares get mushed) Ableton Live tries to get around this by letting you adjust the markers for transients. You would also get such artifacts as sounding "choppy", having a short echo-like effect, and higher frequencies become very stiff and unnatural. A good algorithm will sound more natural, with higher multiples of the original length, but it comes at the cost of more CPU, and even the best ones will still sound somewhat unnatural the more you stretch. Best to try out different types and use your ears.