96 kHz.org 
Advanced Audio Recording 
Sound Generation with Frequency Multiplication During sound generation harmonics of a base frequency might be desired in order to add brightness to the sound. By simple step wise multiplication of the wave value with itself, harmonics can be achieved easily. Each multiplication generates a wave which is shifted up by one octave.
18 Bit precise Multiplication in a DSP: There is only a loss of 2 digits in maximum per step because of the reduction of dynamics by ratio 2 and some offset correction.
Sound Exciting by adding Harmonics 16 harmonics or more can be used to create an exciter:

© 2002 Jürgen Schuhmacher 