Hi everybody !
Yesterday I tried to put the 4 tracks in Ableton, but lengths (and speed on one of them) of these tracks are different…And the sound quality is not very good, seems to have a little time lag.
So my question is, how do you manage 4 tracks imports in a DAW ? And how do you convert AIF > > WAV
Thanks !
Did you check to see if Ableton warped the samples when you dropped them in? I normally un-warp them and trim down the samples. Then determine the BPM of the track and have it set at that.
Thanks for your answer @GCF.
I donno how to see that, I usually don’t use Ableton, but my other DAW doesn’t support AIF format 
I’ve set the same BPM as the OP-1.
How can I unwarp them?
And then for the length ?
I thought about it and I hadn’t used it for so long that I’d forgotten its effectiveness!
thank you @daninski 
It is a little too involved to try to describe. If you set the tempo of the track to the same as the OP-1, then you will want to click on the imported samples and got to the edit portion. Then you can disable Warp. It should match up from there. You might have to move around the samples to get the downbeats to match up. My advice would be to look up some videos on Youtube to get a feel for how to work with audio samples. Here is one: https://www.youtube.com/watch?v=jsHnZUGl8yY
There is also a Coursera course that I just watched that had a lot of good info on working with Live. https://www.coursera.org/course/abletonlive
Go into Live’s preferences, the Record Warp Launch tab, and disable “Auto Warp Long Samples”