In this paper, we present the design and the control of a real-time synthesis model dedicated to percussive sounds. We mainly address the simulation of the "sound colorations" (i.e. metallic, wooden or crystal-clear sounds) independently of the mechanical proper ties of the sound source and their control using a few perceptually relevant descriptors. The synthesis model takes into account both physical and perceptual considerations, leading to a combination of additive and subtractive synthesis processes. The manipulation of the synthesis parameters is not intuitive since the relationship between the parameters and the resulting sound is intricate, especially when dealing with material control. For that, we propose a timbre control space based on the results obtained from listening tests aiming at better understanding how the perception of material in terms of sound colorations can be linked to the synthesis parameters. This timbre control space is mainly based on damping and roughness and allows for an intuitive navigation across different material categories.