When I listen to a recording with very good sampled music instruments, like a piano or guitar for example it doesn’t bother me that much – provided that it’s a good quality sampled music instrument.
However, if I hear the same music instrument in a live situation it really sounds peculiar and bothers me. It seems like the music instrument isn’t in the room, but somewhere else. As a matter a fact, it was! The sampled music instrument was somewhere else when it was sampled. So, it feels more like I hear a recording in a live situation. Soundwise it is a recording!
So, when I listen to a good quality sampled music instrument on a recording it feels more natural since I’m not expecting a present live performance, but a recording that happened somewhere else in another time. That’s probably the reason why I sometimes can accept a sampled music instrument (a replica of an acoustic music instrument) on a recording but not live.
On top of this unrealistic experience of absence, I’ve also noticed that those sampled pianos or keyboards (even the high quality ones) don’t react very well to the performer’s touch. I’ve heard many superb pianists with a beautiful touch falling down to something mediocre when they have to play on a sampled piano or keyboard. Poor pianists, I think to myself when I see them suffer, trying to make music of a dead thing.
Artificial music instruments that aren’t meant to be a copy of real acoustic music instruments don’t bother me at all in a live situation since they are real. These unique artificial music instruments could be more difficult to make sound good in a live situation, though, but that’s another story …