But How Does It Sound?

The challenge of physical modeling, however, is that the model must really sound like the instrument or effect it is imitating. In some cases, particularly with wind instruments, this can be difficult to achieve. Thus, while noise need never be a problem, it can be difficult to generate exactly the right timbre throughout the control space. For this reason, many expressive sound synthesizers employ both modeling structure and measured data. One name for this is structured sampling (discussed further below).