An example of how to analyse the fundamental frequency of two notes being played on a bass guitar.
Documentation on the DFT is available at http://dx.doi.org/10.13140/RG.2.2.33020.05760
Other notes available at at http://pzdsp.com/docs.
Matlab code available at http://dadorran.wordpress.com/2013/12/17/frequency-analysis-using-the-dft-a-practical-example/
A pdf version of the tutorial available at http://dadorran.wordpress.com/2013/12/17/pdf-version-of-frequency-analysis-using-the-dft-a-practical-example/
Download the bass guitar recording from http://eleceng.dit.ie/dorran/matlab/bass.wav