First, the slice function. This is simply incredible. I've now taken 3 drum loops, went to the ZONE EDIT and dialed up 16 zones. Previewed each zone and created new program. Easy as that. I had individual hits for each pad in a new program. The new drum program is named from the original sound and each slice gets the same name suffixed with the number of the zone it was sliced from. This is too easy. I really can't believe it. Another nice thing is when you are back on the main screen, Whatever drum program is assigned to that track, the name shows up just below the track name. (this is the same place each midi channel it's own name).
Time stretching. A few nice things here. One, you can do a straight time stretch to one tenth of a BPM. This is a larger improvement over the former TUNE adjustment to best fit (that is still there, but I'm not sure why). Another, is time stretch to a particular percentage. Actually you can get down to hundredths of a percent here. After you decide what percentage you want to stretch (50-200%), you then pick the best algorithm you want to use suited for the sound you are stretching. The choices are 18 various FEM VOCAL, MALE VOCAL, PERCUSSION, ORCH, STACCATO, MUSIC, etc. and all have A, B or C for choices. A is higher quality and C lowest, but these are inversely proportional to time. And yes, it can take a long time to process the A type quality stretching. On top of that, there is another setting called ADJUST. This is fine adjustment of the presets. High numbers helps highs and perc and lower number helps bass. If you've done any significant amount of timestretching, you should understand this and the limitations. I was actually impressed with some of the stretches I got, but this one is not immune to some of the artifacts that come in of you try to go to extremes.
Resampling. Fairly straightforward. You can lower the sampling rate from 65 kHz to 4 kHz and/or change the bit rate to 16, 12, or 8 bit depth. There is an additional setting here too where you select high, normal or low quality. You just decide how much you want to wait. And the wait was quite long for a one measure loop going from 44 to 30 kHz and 16 to 8 bit simultaneously. Quicker if you don't try to do too much at once. Autochromatic tuning. Easy enough. Just go to the Autochromatic tuning screen, pick a sound you want to use, either with the dial or the pads, select the original key (C01/67 is default), pick a new program name and DO IT. You now have the sound tuned across the 64 pads (notes) of a new program. Nice.
One more improvement over the former model. Purging unused notes. This used to take a very long time, so long in fact, I would restart the machine, which was quicker than purging a bunch of sounds. Not any more.
One thing I would like to see, a cancel button if you get impatient in waiting for the machine to process things like very long time stretches or resampling. All and all, I really like the improvement. Many of the functions I would have to use the computer for, I can now do on the MPC. I've already ditched the computer for sequencing and this newer versatility with the XL separates me and my computer even more. This is my greatest joy. (I know that this sampler engine will not compete with the S models, but it was not meant to).