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Topic: Need data from sound input? (Read 149 times) previous topic - next topic

jacobdensityxvolume

I'm working on a new project and part of it requires an input of the vibration of the air (basically, sound).  I've seen microphones and things like that for the arduino but I'm not quite sure if they can be used to input data of the actual frequencies passing through, to be used for other purposes, or if they only amplify or something like that.  Maybe someone has worked with these before and can explain what exactly they do? Any other suggestions for vibration data gathering?

Paul_KD7HB

Before you get too far into this project, you need to define the range of vibration(sound) you are interested in.

There are very low frequencies elephants communicate with, and then there are sounds bats make to navigate with. Then there are even higher frequencies. Actually there is probably  no high limit.

Paul 

jacobdensityxvolume

It's definitely nothing that extreme.  Specifically, I'll be using tones from a tuba mouthpiece. I just need help with what I should use that can measure constant sound.

Paul_KD7HB

It's definitely nothing that extreme.  Specifically, I'll be using tones from a tuba mouthpiece. I just need help with what I should use that can measure constant sound.
Ok, that narrows it down a bit. Now, what part of sound do you want to measure? frequencies or volume(power)? If frequency, there are fundamental and harmonics in almost any generated sound.

Paul

jacobdensityxvolume

For volume I was planning on using an anemometer.  So I'd be looking to measure frequency, probably just fundamental.

Paul_KD7HB

For volume I was planning on using an anemometer.  So I'd be looking to measure frequency, probably just fundamental.
Sound in air is a compression wave. The actual air molecules move a little one way and then move back a little way. Net is no change in position. The is not the same as air moving through a musical instrument. The moving air creates the sound, but is not the sound. Sound is measured by a calibrated microphone suitable for the frequencies you are interested in.

An anemometer measures air movement, no sound may be involved at all.

Hope this helps a bit. What are you actually trying to accomplish?

Paul

jacobdensityxvolume

Paul, i'm working on a sort of electronic tuba.  I want to use just the mouthpiece and valves and digitize the rest.  Since I'm using only the mouthpiece i think it would work if i used wind speed for volume and frequency for note.  you said something about calibrated microphone, does that mean calibrating it to register the frequencies i'll be playing?

Paul_KD7HB

Paul, i'm working on a sort of electronic tuba.  I want to use just the mouthpiece and valves and digitize the rest.  Since I'm using only the mouthpiece i think it would work if i used wind speed for volume and frequency for note.  you said something about calibrated microphone, does that mean calibrating it to register the frequencies i'll be playing?
All wind speed indicators are rather slow to react to changes in wind. They also have a minimum wind they react to.

Doesn't the frequency of the sound directly relate to the air flow?

All microphones have varying frequency responses. Some have little response at low frequencies. Some cut off response at a high frequency.You need to look at the response curves to see what will best fit your need. Then you will need an amplifier that will maintain the response curve where you need it.

Paul

MorganS

I should think it would not be too hard for a cheap microphone to work with the frequencies produced by the tuba mouthpiece. Pretty much anything will work.

Processing the data to find the fundamental frequency is not trivial. Fortunately there's libraries available to do this for you.
"The problem is in the code you didn't post."

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