Hi Heinrich,

I own a PSR9000 and I can confirm that to my knowledge the PSR9000 does not contain any sampled audio drum-loops. Using the term "groove" is confusing as it is used by Yamaha (and Cakewalk) to describe the shifing of MIDI events to produced a more life-like quality to a MIDI sequence.

If the X1 contains audio drum-loops - (which are variable in speed by time stretching / compression) it is possible that there could be a small loss of quality due to the real-time processing of the audio - however not much.

The PSR9000 drums are, in my opinion, excellent.

However, rather than compare specs, you should let your own ears decide - as only you know what type of style/sound that you like.

Best Regards,

Andy.