There is now a file available for Loksound 8 or 16 mbit decoders for the P40/P42 Amtrak engine. It can be downloaded from the Loksound Yahoo group files section.
I based it on recordings made by Nick O'Dell and furnished by Matt Doti of the compressor and bell, combined with existing Project GE7FL16 engine and Nathan 5-chime sounds.
The compressor makes a distinctive whoop! sound that was nicely captured in the recording.
Hal