I'm going to do a project is that train horn sound detection by detection that sound the Arduino should produce an alarm sound in the speaker actually the concept is whenever the trespasser in train track crossing with headphones playing music in head phone they didn't hear the horn sound so I'm going made an prototype for detection of sound and pause the music in the headphone or make an alarm in head phone for this concept what kind of Arduino is compatible please help?
You mean you want to get to play a sound in a random passer-by's headphones, without physical access to those headphones?
Yes without physical access... Arduino need pause through the headphone mic button
That means you have physical access, or how will you access that button?
I say let the process of evolution take its course, and remove unfit people from the breeding pool.
Train drivers may end up with serious traumas due to this kind of accidents, as are the passengers in the train (they can indeed hear the cracking bones and see the bodyparts flying around - occasionally a train driver doesn't even notice the suicide and the train arrives at the next station all bloodied up).
That's why you want to prevent these accidents. That you save the life of some dumbass in the process, well, so be it.
But we're getting off-topic here. Waiting for OP to let us know how he's planning to tap into the headphones of a stranger (unless "trespasser" refers to him/herself).
What would you propose for the idiots that walk across a busy street, ears plugged into loud music?
I suspect the OP has in mind a program that will be constantly running on everyone's phone (or whatever is playing music) and will sound an alarm in place of the music if it detects the sound of a train horn. And I don't think s/he is planning a system to deter people who are intent on suicide.
To my mind detecting a train horn reliably without false alerts would be next to impossible. And if there are false alerts the warning will be ignored.
But leaving all that aside, the whole idea seems ridiculous when you consider the incredibly small percentage of the population that is at risk of being run down by a train because they did not hear the horn.
I recognize the trauma for the train drivers, but, even so, I think that this is a case where nature should be allowed to takes its course.
...R
Far worse nowadays is people walking with their eyes glued on their mobile phone screen. They don't even need headphones to totally zone out.
wvmarle:
Far worse nowadays is people walking with their eyes glued on their mobile phone screen. They don't even need headphones to totally zone out.
What bothers me most is people using phones (even hands free) while driving.
The fool walking without looking is likely only to injure himself.
...R
As a cyclist I can tell you that those zombies cause a major unwanted adrenaline rush at best... Though it's usually not me hitting the pavement as I generally see it coming (albeit too late for more than bracing for impact) so at least it's not me hitting the pavement.
I've been working on locomotives for 8 years. I've seen a lot of accidents and blood.
Let the people who are dumb do what they want and they'll learn the hard way or they won't be around to learn... win win for humanity.
The last two accidents I've seen were suicide so this project won't help them.
I literally saw ribs hanging from the traction motors last month. Did I clean it up? Hell no. But the locomotive engineers should man up and realize that other people's stupidity is not their problem.
Sorry there was no technical advise in this post.
IS this the same poster from a few years ago that wanted to put a fire siren detector in every car?
Paul
In most rail systems, the train horn is a very specific combination of two frequencies. (Maybe three.) Something like a DTMF decoder could probably detect those two frequencies relatively reliably.
However, that changes as soon as you change countries or move from suburban trains to intercity trains. Then there's a lot wider range of horns to detect.
I've also been to a facility just near the rail tracks which used a train horn sound as the "call the night watchman" alarm. I think it was a horn from a different system, so the man himself could tell the difference but it was quite unnerving pushing a normal-looking doorbell button and having a train horn sound off at full volume just above you.
And to further complicate the detection, there is the Doppler effect on the frequency of the sound. Have to allow for that, also.
Paul
Paul_KD7HB:
there is the Doppler effect on the frequency of the sound. Have to allow for that, also.
No need to bother with that.
If you haven't heard the train approaching you won't be interested in the receding sound 
...R
Robin2:
No need to bother with that.If you haven't heard the train approaching you won't be interested in the receding sound
...R
An approaching high speed train will have a different frequency to a slow moving train.
Tom.... :o
Well, it would help rule out train horns going away from you, so that could be a positive.
I wonder if Raj has enough help, now, to proceed with his project?
Paul
I am not sure if I understand the concept.
a person, only those wearing headphones...
intent on suicide....
walking into the path of a moving train....
should have the music stop playing so they can get the full audible and visual effect of the impact ?