Audio Installation using sensors!

Hey guys!!

fair warning going into this - I KNOW NOTHING! but I'm eager to learn!

I've been given an opportunity to be apart of an adaptive audio installation and in a cheap way create sound effect upon triggering some kind of sensor and I was thinking that an Arduino unit would be perfect for this. I was hoping you guys could give me a hint if I'm headed in the right direction.

the idea:
okay, so the idea is to have an Arduino unit with an audio shield (?) on top and be able to take the input from say a motion sensor and trigger a sound effect on the stored SD card that would then be output'd into a set of active speakers using a regular old audio jack (3,5mm)

the concept is pretty simple, however I want to use the MAX/MSP as the "audio plattform" as I have some experience with that on the PC/mac.

and before going out and buying the things i want to know if you guys have any tips or any better ideas of how to acheive a better sound installation.

so, some questions are:
1.is this a valid concept?
2.are there any other sensors that could be used except motion? to trigger when someone enters the room (kinda)
3. is there any limitations with using the Arduino unit in this way?
4. how far away can the unit be from the actual speakers and sensor?

I'd love to hear from you guys! please help :D:D

Best regards
Jesper

okay, so the idea is to have an Arduino unit with an audio shield (?) on top and be able to take the input from say a motion sensor and trigger a sound effect on the stored SD card that would then be output'd into a set of active speakers using a regular old audio jack (3,5mm)

1.is this a valid concept?

Yes.

2.are there any other sensors that could be used except motion? to trigger when someone enters the room (kinda)

For a person entering the room, motion sensors are very common on alarm systems. Or, you can do an light-beam or floor mat etc. Anything that puts out a signal could be used. You could even use a sound sensor, but since your setup makes sound you'd have to be careful about it triggering itself... ;D

  1. is there any limitations with using the Arduino unit in this way?

Yes. There are always limitations... There's a limited number of inputs, the audio shield usually requires a special filename format, there's usually a limited number of files, it's stereo or mono (no 5.1 or 7.1 surround) and there may be other limitations depending on your requirements.

  1. how far away can the unit be from the actual speakers and sensor?

How far can you run wires?

the concept is pretty simple, however I want to use the MAX/MSP as the "audio plattform" as I have some experience with that on the PC/mac.

I don't know anything about MAX/MSP, but as far as I know, there is no compiler for the Arduino. You are better off learning C/C++.

For what you've described, the programming should be simple. The audio shield has it's own "brain" and it's own sample-rate clock, so all you have to do is send little messages like what file to play, etc.

MAX / MSP has a graphics interface, there is no way you can run it on an Arduino. You can send messages into MAX from the Arduino through the serial port. Either as MIDI, OSC or simple serial. The simplest way is the USB cable but wi-fi and Bluetooth are an option but it is more complex.

A wav shield will do but perhaps simpler would be a MP3 card as it uses less of the Arduino's memory.

Thanks so much for your responses!

For a person entering the room, motion sensors are very common on alarm systems. Or, you can do an light-beam or floor mat etc. Anything that puts out a signal could be used. You could even use a sound sensor, but since your setup makes sound you’d have to be careful about it triggering itself… ;D

A beam sensor might actually be better for a more precise motion detection, however doesn’t the emitter and received have to be mounted very exactly in order for this to word? is is there maybe some spread of the IR light?

Yes. There are always limitations… There’s a limited number of inputs, the audio shield usually requires a special filename format, there’s usually a limited number of files, it’s stereo or mono (no 5.1 or 7.1 surround) and there may be other limitations depending on your requirements.

This shouldn’t be an issue, we’re going to use standard stereo wavs matching the specs of the shield :slight_smile: good point though thanks.

MAX / MSP has a graphics interface, there is no way you can run it on an Arduino. You can send messages into MAX from the Arduino through the serial port. Either as MIDI, OSC or simple serial. The simplest way is the USB cable but wi-fi and Bluetooth are an option but it is more complex.

OOooohhh I thought that a simple version of the GUI in MAX/MSP was able to be run straight on the arduino. but then as DVDdoug said, I’d be better of learning some C/C++ shouldn’t be to hard to code.

last questions then…for now

is there anything else I need before going out and buying the components, like do I need to solder any of the components? or is all the nessecary components in the box straight away or do I need to buy some “getting started kit”?

Please see the attachment for what I currently have in the cart. any good advice on where I can find some other sensors? I live in Sweden btw, so international shipping is a must :slight_smile: (I couldn’t find light or motion sensors on this site :frowning: )

Thanks again
//Jesper

Capture.JPG

A wav shield will do but perhaps simpler would be a MP3 card as it uses less of the Arduino's memory.

Good point, however the unit would only need to play a short sound effect maybe two, there shouldn't be any memory issues.

like do I need to solder any of the components?

Yes all of them.

however the unit would only need to play a short sound effect maybe two, there shouldn't be any memory issues.

The simple fact of including the filing system capable of reading an SD card takes up a large amount of memory.

However short sounds, about 3 seconds worth can be stored in the Arduino's program memory and produced without a wave shield, see:-

I would hang on and get your design sorted before buying anything.

The simple fact of including the filing system capable of reading an SD card takes up a large amount of memory.

However short sounds, about 3 seconds worth can be stored in the Arduino's program memory and produced without a wave shield, see:-
Arduino Uno saying Yes & No without extra hardware - YouTube

I would hang on and get your design sorted before buying anything.

Oh, okay - however the exact sound effects havn't been determined yet, so they might be longer than a few seconds. The concept, would be viable for a couple of sound effects that might need a few seconds. maybe even a up to a minute.

should I then look into the mp3 shield instead?

It depends on what else you want to do on the Arduino.

My part in the project would just be that, using a sensor to trigger sounds effects that would then play in a set of stereo speakers :slight_smile:

OK so you should be fine with a wav shield then.