Frequency Analysis

I had posted a topic earlier this year about taking audio input, and measuring the frequencies of the sound in order to create one of those audio visualizer, but was unable to really find anything i thought would work in the way i needed. Since then i have discovered two new things. One, called FFT, which a library for arduino has actually been written to do, but i don't know if it is small enough to work properly. The other called a Fliege filter, which i found at http://www.instructables.com/id/Nixie-Tube-Music-Visualizer/?ALLSTEPS, and i think i like the fliege filter enough to give it a shot. Only problem is that it is designed to output 0-12 volts, and the last part of the circuit is designed to change that to current. I know how to fix that, so that i am outputting 0-12 volts, but seeing as the arduino inputs 5, and i dont want to cut off the top , i really want to scale the output down to 0-5 volts. But i have very little clue as to how this works, and how to change it. Any ideas?
bman22

Posts: 75
Joined: Mon Dec 22, 2008 2:38 am

Re: Frequency Analysis

I don't know how much you can get online without logging in but this might put you on the right track.
http://nutsvolts.texterity.com/nutsvolts/200801/?pg=56&search=color%20organ&per_page=5&results_page=1&doc_id=-1

franklin97355

Posts: 21488
Joined: Mon Apr 21, 2008 2:33 pm
Location: Lacomb, OR.

Re: Frequency Analysis

A voltage divider would seem to be the most direct approach. Have you considered that?

zener

Posts: 4555
Joined: Sat Feb 21, 2009 2:38 am

Re: Frequency Analysis

i did concider that, but is that the simplest method of dropping the voltage?

I looked and now realize i don't know what i am looking for. do you think you can provide an example?
bman22

Posts: 75
Joined: Mon Dec 22, 2008 2:38 am