I don't think so! A fatter string requires more tension in order to make it's higher mass resonate at a given frequency. More mass and tension require more energy for the same amplitude. Apart from the fundamental tone, harmonics appear along the string. The more energy, the more harmonics. As those harmonics are multiples of the fundamental frequency, the result will be a richer tone, not a fatter tone. As the proof of the pudding is in the eating, I analysed the waveforms produced by