hello i'm trying to implement a distortion for guitar with waveshapes like: f(x) = ((1+A)*x)/(1+A*fabs(x)) or f(x) = x*x*x/3; the problem i'm having is that, for low frequencies (bass), the sound is strange... it tends too much for treble (not exactly treble, but more likely a medium frequency) and doesn't sound good... at the same time, I can't cut those frequencies because, since it isn't "too treble", I'd lose interesting frequencies when playing other strings anyone has some suggestion on how to "fix" that? Thanks in advance and sorry my English
bass distortion
Started by ●November 17, 2004
Reply by ●November 18, 20042004-11-18
Hi Luis, these two types of distortion will create only odd harmonics which might or might not be what you want. Try using a distortion that creates odd *and* even harmonics for comparison, maybe this is more to your liking. Also, if you use Chebychev polynomials as your nonlinear transfer function you can create exactly those harmonics that you want. For example, the second-order Cheby poly f(x) = 2x^2-1 creates the second harmonic, the third-order poly f(x) = 4x^3-3x the third, the fourth-order poly f(x) = 8x^4-8x^2+1 the fourth and so on. That way you have better control over both the bandwidth (important for aliasing considerations) and the harmonic content (important for the sound) of your output signal. Hope this helps -- Stephan M. Bernsee http://www.dspdimension.com