In the past we have touched on cheapish ways to get loco sound, without going to the cost and complexity of MLS, etc. Pesonally I had some success with Rik's recordable greetings cards modules but thay do fail quite quickly. This morning, whilst looking for something else, I noticed this "Adafruit" module which seems to be almost exactly what we need.
https://thepihut.com/products/adafruit- ... 7gQAvD_BwE
Of course, it is more expensive than the greeting cards module but then again is likely to be longer lasting! There are apparently quite a few variations available and I doubt that we would need the twin amp/speaker version, https://learn.adafruit.com/adafruit-aud ... d_products
but they are all fairly small and self contained, needing only 5v power and a button to ground, to trigger the operation - it doesn't need any other microprocessor module, and they say that using a WAV file on loop there is only an imperceptible 20ms gap between repeats. I'm guessing that one of the Deltang outputs could provide the on/off grounding signal and since it can hold half a dozen or more sound files, whistles etc, might also be achievable.
They have apparently been around for over 10 years so dunno why we don't seem to have noticed them before, but maybe I'm the only one who has missed it!.
