Hi, I am building a trackless train that I want to be able to press a button and a specific audio track is played. since this is used at festivals and the ambient noise level is high I wanted to use a marine amp and speaker system. 1 speaker in each car and 1 in the engine. how would I go from the mp3 board to the car amplifier. the train will be wired for 12v. any insight would be appreciated.
thanks
Donald
I’d use a ground loop isolator between the amp and the trigger board. Then connect that to the input on your amp with whatever cable it needs to go between a 3.5mm socket and the amp.
Something like this should work.
Thank you for the direction, I’m fairly new to working with small electronics, I usually follow tutorials to do what it is I am wanting to do, but I couldn’t find anything on YouTube where someone hooked up the spark fun player to a car amplifier.
The [MP3 trigger/13720 has a standard 1/8" TRS (stereo headphone) audio connector and the datasheet says the outputs provisioned are suitable for 30Ω loads. That’s easily enough to drive an automotive (or almost any other) amplifier with only some regular audio cabling.
Assuming there’s power available, I’d consider an amplifier for each car. This will make it easier to wire initially, easier to expand or reduce the number of cars, and also allow different audio levels. For example, the train operator doesn’t need the audio very loud most of the time; they’re heard it a million times before, but the guests need to be able to hear. There are a bunch of little ones with wide input voltages and various input techniques (USB, RCA, Bluetooth, etc) and, it must be said, likely ‘optimistic’ specs. Here’s one I’m posting for no other reason than the big knob but you can use a far cheaper amp:
https://www.amazon.com/Nobsound-Bluetoo … 07DQFRGT2/
The ground isolator can’t hurt but I’d see whether it’s needed before buying one.](MP3 Trigger - WIG-13720 - SparkFun Electronics)