I was wondering if there was any way to replicate the echo heard while your driving in a tunnel/ under a longer bridge in-game. Or is this technically just not possible in the Trainz engine?
I think there are some track types which feature a change in sound, but the acoustic "occlusion" under bridges/tunnels or indeed narrow cuttings that can be set up in the other two big sims, simply doesn't exist per se in Trainz.
While I feel that TANE is a huge step forward in many aspects, the sound engine still has much to be desired. I use a semi-pro audio interface and experience sound cutting out much too often (particularly rolling stock when observing from a stationary point)
I use a track made by HP called bridge sound. It mimics a thundering noise that can be interpreted to what you hear passing a tunnel or bridge. And I have asked for it many times in the past. Is this so hard to do? Apparently proper sounds is not a priority for otherwise an excellent game..