an omnidirectional microphone

Hello! I just started preparing an item, and I will need a microphone later on to register the volume and to use it to light up some leds. Kind of simple when it comes down to the software, but I am not sure of which microphone to use. I know it should have a max voltage of 5. I have seen some of the thredas but they involved too many complications, while this mic I found might actually work just the way it is, with its small metal legs.

My question is, will this mic work if just connected to an arduino? What's with all that talk about amps?

Features omnidirectional type high sensitivity, flat frequency response, light very reliable and shock-resistant

Specifications miniature size: 10mm impedance: low standard voltage: 4.5V current drain: 0.5mA S/N ratio: 40dB or more maximum input sound pressure: 120dB SPL sensitivity: 0dB = 1V/1[ch31026]ar, 1KHz Vcc = 4.5V, RL = 1K Ohm

Thanks for your advice.

The voltage refers to the voltage you need to power the microphone not the voltage the microphone produces. That is likely to be in the order of a few tens of millivolts and so you will need an amplifier if you want to measure the output on an arduino. Also if you want to measure the sound level then you will need a peak detector circuit after the amplifier.

where am I supposed to get these two? amp and peak detector? What happens if I only have an amp? will it not notice the sound at all then?

What is the easiest possible way to get my arduino to notice sound? I am none too good with the electronic bit, at least not yet, and I can't find a good tutorial that is really for newbies.

Thank you a lot for your help, it was very much needed.

This is not exactly a tutorial, but is still the best introduction site I found about electronics : http://www.allaboutcircuits.com/. For this specific matter, look at III, 8.

thank you very much for your suggestion, but oh my goodness if it isn't long... I want to get it started right now! I don't understand why this site doesn't have a tutorial with pictures like it has for everything else. I just need to know what to buy and how to connect it so that my arduino gets the volume. This will take ages... :'(

Mmmh… maybe this could help. http://www.allaboutcircuits.com/vol_3/chpt_4/5.html

hmm, read a bit of it, and am still dumbfounded. I just need to know like, "buy a mike, connect it to an amp, in a series say, and then connect the amp to the arduino pins this and that, and it should read volume with the right software". All these graphs are very hard for me to read, I prefer a word description or a picture, nowadays that digital pics are so easy to take. But there is nothing like that in the whole wide web. Tough for me!

Hm, ok, I have checked around a bit, and here is something that might work

http://www.electrokit.se/download/FK648E-1.pdf

is this something that could just connect to the arduino and give me my volume signal? I don't really care whether it checks volume or not, I just want to have a signal when the mike detects some sound.

thanks again for all your support!

Tom Igoes book "physical computing" has a chapter on sound detection and interfacing microphones.

I have found this book to be a goldmine of infomation on interfacing just about anything to a microprocessor.

for easier understanding of what my question is, the link above is describing an electret microphone. If anybody knows whether or not it can be connected to an arduino and just work, without further electronics needed, please tell me.

for easier understanding of what my question is, the link above is describing an electret microphone. If anybody knows whether or not it can be connected to an arduino and just work, without further electronics needed, please tell me.

Simple answer - no it won't work with out an amplifier.

if you read its description it says that there is an amplifier in it.

It wont work without an amplifier. But the amplifier can be very simple. You can build it based on the LM386 OpAmp and just a couple of other components.

if you read its description it says that there is an amplifier in it.

Yes but you still need a peak detector. You can make one by taking the output and putting a 10K resistor to earth, and putting a diode across it with the anode to earth. Then take another diode with the cathode to the output and the anode to the arduino pin. Finally a capacitor say 10uF from the ardunio pin and the anode to earth. Then you might get something and not damage your arduino.

Oh, thank you very much! That is a good solution!

After doing some of my own research though, I am now more interested in a contact microphone (like a piezo speaker), which would anyway read signals of up to 90 dB and wouldn't need an amplifier. At least according tomy sources. Still researching it. I want reallt to have as little unnecessary hardware as possible, so as long as there is something that notifies me that there has been a sound, I will be satisfied.

Still researching it. I want reallt to have as little unnecessary hardware as possible, so as long as there is something that notifies me that there has been a sound, I will be satisfied.

This is what is known in professional circles as producing a specification and it is one of the hardest thing to do. As all thing are possible a good designer is one who knows when to stop. Beware "feature creep", tempting though it is. Then you have to balance what hardware will or can do and what you can leave to software. Remember software costs time but once it's done it costs no more. Hardware reduces the amount of software you need but has to be payed for on every one you make. You now have to decide what is the lowest level of sound you need to detect, there is a practical lower limit with any system what does it need to be on yours? Then you can decide how much you need your transducer amplifying. Remember it's not just the maximum the dynamic range to consider. It is possible to make things too sensitive as well as not sensitive enough. Anyway best of luck with your project.