I need to say this method is extremely accurate for simulating the way the dual engine locomotives were operated.
My buddy and retired engineer RC Smith who actually piloted EMD E-units for the Pennsy, Conrail and CSX, as well as my copy of the DDA40X operators manual, confirm the two prime movers were operated as two independent engines each having their own control panel and start button.
I have no reason to believe an Alco, Baldwin, or GE would be otherwise.
The technique to create your own Dual Prime Mover file for the LokSound V4.0 is pretty simple.
Open the desired single prime mover file in LokProgrammer and go to the Sound Tab.
Copy the entire flow diagram (<CTRL A><CTRL C> on the keyboard) of Sound Slot #1 and paste it (<CTRL V>) into Sound Slot #2.
Then edit the Transition Table for PM#2 adding 2 or 3 points to each transition step value.
I also like to compress the range from bottom to top so the prime mover spools up more quickly.
Be patient after copying the flowchart and the transition arrows will automatically connect to the Mute container.
Also be sure to delete any stray containers that might be created.
Sidenotes...
This is how you adjust the speed at which any prime mover spools up in a LokSound. There is no single CV as in other brands. It has to be done inside the sound slot flowchart.
If using the ESU LokSound V4.0 and you do not wish to start two engines or to allocate two FN buttons to engine startup, simply map both slots to the same FN button. When you select that FN in operation, both slots will be activated... but it's not as cool.
This same technique can be applied to horns to simulate the dual chime effect in the DL109 example that follows. From my limited research many locos used multiple notes of the so-called "blat" horn in the pre-three chime/five chime horn days to create distinctive sounds. Load the horn .wavs into two unique sound slots then assign both slots to the same FN button.
