Lets not overlook the midi performer, not as a technician but as a musician.

For discussion lets assume he/she is an excellent piano player.
No doubt the selection of a midi keyboard and appropriate piano sound library will be informed.
Most of their performance using midi will probably be within the realm of realistic piano playing.
"Believeable" if you will.


Now lets assume they want a Hammond B-3 with a leslie speaker sound.
A keyboard yes, but a very different type.
The fully weighted 88 they bought for Midi Chopin Etudes may be useless for playing Jimmy Smith lines.
Even with the right keyboard and library, there's no guarantee his organ stuff will ever be believable.
He has to think like a B-3 player. He has to know the sound he's after.

Consider the same player with a brass library, violin, or heaven forbid, a pedal steel library.

There's no telling what will come out. Some of it may be good.
Some may be less than good.
It may not be the "fault" of the library, but the fault of the musician.
Even though they are a great piano player, their pedal steel stuff may just suck.
Its really easy to suck on a pedal steel. I did for years.

One definitely wants high quality sampling of both the timbre of the instrument as well as the technique/embouchure of a good player in the midi library.
This costs money and is worth it.
JazzMammal hit the nail on the head.

A midi "player" ALSO needs some understanding/sympathy of the instrument in question to generate believable music.
Just because your midi keyboard has a pitch bend wheel does not make you Jeff Beck.

Midi- with great power comes great responsibility.

just my $02.

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