For about seven years I have had a lot of fun manipulating sound, or more specifically sound generated from a software synthesizer I am programming, with DSP \u2013 Digital Signal Processing. For my synthesizer I have programmed not just tone generation via multiple synthesis methods, but also modulation, effects, and filtering of those tones.<\/p>\n\n\n\n
In the past I have tried out new DSP code ideas directly in Visual Studio, compiling the C\/C++ code, and then open my VST3 plugin in the Reaper DAW software., However, I recently came upon \u201cFormula\u201d and VST or stand-alone program that allow one to quickly create and test DSP C code within the App. You may find information about \u201cFormula\u201d, including a download link here; https:\/\/soundspear.com\/product\/formula<\/a><\/p>\n\n\n\n The App itself contains, at the time of writing, about formulas, pieces of C code, anywhere from filters, to delay, chorus, reverb, and distortion. One of these included formula\u2019s, are \u201cFormant vowel\u201d which is a formant filter that can make a waveform such as a sawtooth, sound like a person speaking vowels. I incorporated this into my synthesizer, and quickly expanded the code from being able to \u201conly\u201d generate 5 vowels via a cutoff parameter ranging from 0 to 1, to code that could smoothly mix between two adjacent vowels. It sounds cool when applying an envelope, and\/or LFO to the cutoff frequency. As I was unable to submit my enhanced version to the developer, I am publishing it here on my website for anyone to use as they wish.<\/p>\n\n\n\n Note if you’re not using the “Fomula” app to test this, you need to replace “KNOB_1” with your variable holding the current cutoff frequency, from 0.01f to 0.99f.<\/p>\n\n\n\n