Is there anyway to insert new voice files for new occations?

[EurekaSeven]

I'm having a idea of separating the "missile launch" sound file in Air combat for 2 differnent specific occations depending on whether the missile is targeting interceptors or UFOs, so that i can insert some new sound effects into the new missile sounds (like calling out FOX 3 if Interceptor firing torpedos, FOX 2 while firing standard missiles, or Missile Alert if the UFO fires one), is there any idea to create or separate sound files to a given new occations for playing it?

Also, would X2 having the same system of sounds and musics as gc.xml, so that the music replacement mods in X2 won't need much change from X1 mods?

[Solver]

You can only replace existing sound files, there's no way to control any logic or do anything more sophisticated there.