I am in the need of a really simple mp3 player that I can start form a simple short connection.

It's for timing fireworks to music, so I need the mp3 player to trigger from our firework trigger system.

My Google-fu hasn't turned up anything yet, but I thought this could be the perfect place to ask

Cheers

Cris

Maybe you could modify something like this?

EDIT: Cheaper here and looks a bit simpler.

I'm trying to infer from context here that you're looking for a physical portable MP3 player device, right?

Most iPods can be controlled by a button on the headphone cable.

If you look closely, iPod and iPhone headset plugs, the ones with the inline button dealybobs, aren't just tip-ring-sleeve, they are tip-ring-ring-sleeve. That extra ring is for the control interface. I think it's just resistance values, and you could wire up something that fired off the iPod on command pretty easily. I'll see if I can find a resistance value reference.

This Thread implies that if you merely want play/pause, you just short that extra ring to ground briefly.

If you want more fancy, you need more circuitry to control the signaling on that connector.

If you could use a little laptop/netbook as an MP3 player, one idea is to take apart a USB Mouse. You could just take the wires for the short connection, piggy them up to the left mouse click button and probably blind out the sensor/take out the ball whatever as well.

Use the trackpad on the laptop to hover over the 'play' button in your MP3 player software and your short out connection should hit the button for you. Hopefully.

Although you will need to release the short connection for the mouse click to register.

I was really looking for something a little more robust, like an embedded solution. This is going to be used in some pretty terrible conditions, and wired to a PA of some kind. So I wanted something I could just hook upto without any dodgy homebrew wiring.

Raspberry Pi?

Audio out - should boot very quickly - runs linux - designed for I/O control.

Maybe you could put a kit like this into a weatherproof box?
http://www.quasarelectronics.com/velleman/k8095-mp3-player-kit.htm

I think a solid-state MP3 player such as an iPod Nano would be the most robust, then. Triggering its play button via a relay connected to its headphone jack would probably be the most reliable thing. And because solid state MP3 players are cheap and plentiful, you could, in theory, have multiple hot spares on hand if one malfunctions.

What you haven't described is the mechanism by which the fireworks launch system can trigger the play function on the audio. Is it a relay wired up to a connector or what? I don't know what these systems look like. You'd think that if the system had a way to trigger audio-start, that they'd also *already* sell an interface just for this purpose.

Much as it pains me to suggest it....but....

http://www.sparkfun.com/tutorials/295

Arduino + MP3 Player Shield + minor effort will allow you to do exactly what you want. Stick it in a case and you should have a pretty robust system.

This looks the ticket! I'll look into it

This is what will trigger it...

http://www.cobrafiringsystems.com/index.php?route=product/product&product_id=51

I think they are working on their own solution for this, but I want something to work with now.

Cheers

Cris

You could try this.

Seems to do what you need.

pca

Or just buy something made for the purpose...

https://www.gilderfluke.com/index.php?ma...u34hl9bi3b4nl5p

That would be just perfect, if it could read from a USB Flash Drive! Bummer. I'll keep looking.

Surely you can just stick the microSD card into a USB adapter ?

http://www.sparkfun.com/datasheets/Widgets/MP3Trigger/MP3TriggerV2UserGuide_2010-07-30.pdf

Yea, I could, but the mounting options are limited for SD, and in the conditions it's going to have to work under I would much prefer to use a robust USB key to hold the tracks on rather than a tiny and very easy to loose micro-SD. I might give this trigger mp3 a go as it's perfect in every other way, and pretty cheap!

Cheers

Cris