Breath/Wind Sensor?

Hi I am working on a project for a client where the viewer blows into "something" and it increases voltage the harder one blows. At first we tried a mic but then the obvious problem is that if you talk into it that as well creates amplitude and we only want the act/pressure of blowing to create data.
Any suggestions?
One thing I though of was having a little ball in a tube that is infront of a proximity sensor. When u blow the ball moves up towards the sensor creating data, but that is a little to carnival ride for me and might not even work.
Lemme know,
-M

Sounds like you need a pressure transducer. Do a board search for "pressure" and you will probably find many post.

I've seen this kind of project don't before. A small DC fan is used. The user blows into that and the resulting output is translated over to a larger fan. Output is generally detected by an IR sensor reading how fast the blades are breaking the beam.
http://blog.makezine.com/archive/2009/07/breath-over-ip.html?CMP=OTC-0D6B48984890

Blow a straw over small paddlewheel that has low friction and a simple rotary encoder pointed at the wheel, counting the revs of the paddlwheel.

David

There you have:

iua.upf.es/~jlozano/interfaces/blow_sensor.html

Another way to do this is to use a "hot wire anemometer":

It's basically a resistance wire that is heated by passing a current through it. The air passing over the wire draw away some of that heat, and the wire cools. Now, the resistance of the wire changes with temperature! So by keeping the current constant, and measuring the voltage across the resistance, we can measure air flow.

There was a small circuit for doing this in Elektor last year. They used a small filament light bulb (a 12V car-type bulb, I think) and a simple constant-current circuit. The varying analog voltage can be read by the Arduino's analog input pins, of course.

here ya go:

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