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By ryurkovich

I am using an "MP3 Trigger board" with a "Dayton Audio DTA-1 Class D AC/DC Battery Powered Mini Amplifier 15 WPC" I sourced from Parts Express.
The audio plays fine until I hook up the button for the trigger.
The issue seems to only happen when a long wire (~30 ft) 16 gauge speaker wire is hooked up to the trigger, and the other end to a push button.
It gets triggered randomly even when the button isn't pressed.

How can I prevent this from randomly being triggered? and the long wire is necessary.
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By robertsonics
How old is your MP3 Trigger? The latest version (with the solder jumpers SJ2, SJ3 and SJ4 in the analog output section) has a pull-up resistor on the output of the multiplexer to help with the long wire issue. If you have an older version, there are posts around describing how to add the pull-up.

An easier solution is to use triggers 17 and 18, which don't go through the mux.

That said, 30 feet is kinda long for a 5 volt input. Noise can certainly be a problem.
By ryurkovich
I believe I got the MP3 Trigger in the last month or two. WIG-13720 is on the packaging.
I'll try out the 17/18 pins and see if that resolves the issue. I found a post about adding the pull-up resister so can try that if this fails.
Would you recommend using something else instead of the mp3 trigger? We have some inputs that will need to be up to about 70 ft.
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By robertsonics
If your MP3 Trigger is that new then it already has the pull-up. I suggest trying triggers 17 and 18 - they'll definitely be better, but will still trigger on significant noise, and 70 ft of wire is a bit antenna.

Both the WAV Trigger and Tsunami have input debouncing, whereas the MP3 Trigger just looks for a transition of any duration. Moreover, both have an undocumented init file command for adjusting the trigger debounce time:


where "n" is the debounce time in milliseconds. For such long wires, either would be a better option than the MP3 Trigger.
By ryurkovich
Thanks. I looked into the Tsunami Super Wav Trigger player and it seems like it could be more helpful since we need 5 separate speaker outputs and this at least offers 4.
Sparkfun tech help also suggested getting shielded cable? Do you think that would help? Trying not to spent too much more money here.
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By robertsonics
Possibly, but you have to be very careful with how you connect the shield - it can also become an antenna. But it really depends on how tolerant you are with occasional false triggers. You might eliminate most but not all. Again, that's a really long run for a 5V digital signal without debouncing on the inputs.

Tsunami actually has 8 audio output channels that can be configured as either 4 stereo or 8 independent mono outputs.
By ryurkovich
I see that the Tsunami player has L and R for each of the audio outputs, but don't see a way to make a specific trigger only go to say Output 1 Left? or is there a way?
We have 5 separate speakers that correspond to the 5 separate buttons (Each button plays the sound in the nearby speaker)
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By robertsonics
There two versions of firmware for the Tsunami - stereo and mono. The Configurator app supports both versions. See the download page. The former plays stereo files which can be directed to any of the 4 stereo pairs. The mono version plays mono files which can be directed to any of the 8 mono outputs.
By ryurkovich
I am trying out the Tsunami player (in mono mode) so that i can play all of the tracks off of one player.
Here is a link to a OneDrive folder with files of the schematic of how I plan on setting it up, and the files I put on the SD card: .ini file, and the audio files. ... A?e=anc3L2

I can't get sound to come through with my initial testing with short wires. Do you know why this may be?