Thanks. It's almost impossible to fool people who actually play the instrument. Besides sample quality you also have to think like a player of the instrument and if you can do that you just play the part yourself. Anyway, as long as it doesn't sound so fake that it ruins people's enjoyment of the music it's good enough AFAIC.
The problem with simulating brass instruments, particularly trumpet, even with high quality samples is that there are so many variables and nuances in how the notes are attacked, released, transitions between notes, various inflections.
If you strike a piano key over and over the same way, pluck a guitar string, bow a violin note the same way it sounds fine. If you do it with a trumpet sample it sounds robotic. The mechanics of double and triple-tongued notes for example is very different than single-tonguing and the sound is different and can very readily be heard.
Trying to simulate legato or slurred notes is about impossible because of the mechanics of the instrument and the way the embouchure, tongue and breath create the sounds. Some notes are transitioned between by use of the valves, some by utilizing only the harmonics of the instrument, which you'll never simulate using individual tongued samples. You don't even have to use the tongue, you can do a breath attack.
You basically have to record a bunch of individual articulations of various lengths and transitions between notes at various tempos but to make a comprehensive library of such samples would be all but impossible and prohibitively cumbersome to actually try and use.
Where you can come closer is with simple passages that don't use much in the way of articulations, particularly an ensemble sound but that obviously seriously limits what you can do.
Here's some french horns that came out pretty decent. Low brass seems to be more conducive to simulating.
View attachment midihorns.mp3
