Abstract
A system for morphing the brightness of two sounds independently from their other perceptual or acoustic attributes was coded, based on the Spectral Modelling Synthesis additive/residual model. A Multidimensional Scaling analysis of listener responses showed that the brightness control was perceptually independent from the other controls used to adjust the morphed sound. A Timbre Morpher, adjusting additional timbral attributes with perceptually meaningful controls, can now be considered for further work.