sound, followed up by an optional pitch and volume.
Values of 1.0 are the defaults.The range of volume is from 0.0 to 1.0.
The range of pitch in note_block is from 0.5 (2^(-12/12) ) to 2.0 (2^(12/12) )
A full list of pitch value can be found on the Minecraft Wiki: Note Block
Pitch can be applied to any sound effect(some effects will be accelerated)
Use msound to play the sound every tick while a train is moving on top of it.
Use sound in to play the sound only to player passengers of the train.