Great mod this but I'm using a mod (Yuoki) which adds various steam trains to Factorio so the default honk sound doesn't fit these. It would be nice to be able to configure (in Settings?) or have a second command button (say J) for steam train whistle. Wish honks were in vanilla, they're an obvious feature.
Sound effect example:
https://freesound.org/people/eliasheuninck/sounds/170848/

Hey, thank you for using the mod. I'll look into implementing a secondary sound soon. It will probably be doable to add a second button, but I'm not sure if I can detect trains other than vanilla ones.

I'll keep you posted.

Greetings,
Theelicht

Hii,

It's been three years, but I'd figured I owe you an answer. You could download the mod and swap out the audio file locally (I know, it's a boring answer).
Earlier this week I started playing again myself. I'll have a look into adding a settings menu for the sound.

^.^