FFT Analysis for Dummies
2010-03-27 20:41:30
Folks, I'd like to learn more about FFTs. I'm not a math guy, so I imagine I'll never fully understand all the nuances. But I'd like to try anyway. I understand the general concept, that an FFT shows how much energy is present at different frequencies. What I'd like to know is how to set the various parameters such as FFT Size and Overlap, when to use the different types of window smoothing and why, and so forth. Below is a list of settings in the Rightmark FFT analyzer with my associated questions, and hopefully this is a good place to start. [blockquote]FFT Size: I understand that the higher the number, the better the frequency resolution. So why is this even adjustable? Why not just use the highest resolution possible automatically? Zero Padding: This ranges from None through 8x. What does this do? FFT Overlap: What is this for, and when would you use higher or lower values? FFT Window: I recognize some of the names, but have no idea when or why one would select these choices. Kaiser Window beta: I have no idea what this does either. I noticed that Sound Forge lets you pick the number of slices to show. What are slices and why is more than one needed to analyze a Wave file?[/blockquote] I realize this is a lot to ask! If anyone knows of a good newbie-level tutorial that explains this in plain English with minimal math, I'd love to see it. Everything I've found through Google starts right in with math that's way over my head. --Ethan