I have an idea for a project.
I recently installed a car stereo amp.
I wish to create a combination Ampmeter + Voltmeter that will calculate the actual Watts/Power output to one speaker and display it on an digital display.
I intend to use one Fio board as the sensor/sender attached to the + speaker wire in the door - powered by the 12v car circuit and another 12v Fio for the display/reciever on my dash.
Ideally I want to display Wattage and be able to calibrate the display to the max power and switch between Watts or a display of percent of max.
I have a basic understanding of circuitry (I am an engineer) but I don't know digital control and I am not a good prgrammer.
This is my first Arduino project, and I realize I am kinda jumping in at the deep end of the learning curve.
I just want to know if what I propose is EVEN possible before I start a long fruitless project.
Yes it is possible but there are many different ways of defining audio power. Not all of them are related to perceived loudness in a way you would expect so I am not sure what the point of the project is.
measuring power in an AC waveform will require external circuitry like a true RMS converter chip:-
http://uk.farnell.com/analog-devices/ad536akh/true-rms-to-dc-converter-ic/dp/2229195
Likewise measuring peak power would require a peak detector and so on.
The project is not about loudness.
It is intended to provide a geeky gauge on my dashboard that will indicate actual electrical energy being sent to the speaker from the amp.
My stock Subaru radio is rated at 40 watts. Until I found that out I wondered why the volume knob went from 0-40. I don't like having to calculate in my head that when the knob says 10 it actually means 25% volume, what does 13 mean - that is too hard for this engineer to figure out without my trusty calculator.
My new amp is 65W RMS - 110W peak. I used to work at Square D installing High-Power Circuit breakers and Voltage and Amperage gauges. I know my circuit needs to have a fat wire passing thru an electromagnet ring to detect amps and a voltmeter attached to the ends of the fat wire to detect voltage. But I have no idea how to create a digital meter or have the ARDUINO multiply the two values to arrive at watts. I know calibratation is important because I don't want to burn out my circuit the first time I PUMP IT UP.
Any help to get me started in the right direction for detection hardware would be helpful. In the mean time I will give myself a crash course in programming the ARDUINO Fio.
Thank you for your quick reply!