Hello everyone, The sum of two sine waves that have close frequencies can produce an Envelope Wave: http://en.wikipedia.org/wiki/Envelope_(waves) What formula can I use to turn it into one wave (i.e. one frequency and amplitude)? Example pic attached: The blue "Envelope Wave" is actually 2 sine waves combined. And the green sine wave is what I really want. Finally, I am curious to know the proper keywords that would have allowed me to find this formula on Google, or are there not any? Thank-you very much.