Only if they retain their original shape. The point is not that any wave is a soliton, but a soliton never changes shape as it moves (through time, a medium, or whatever). The soliton can decrease in amplitude, and expand in width, but otherwise remains the same.

A pure, single Gaussian hump is the soliton for homogenous linear media. If you create an audible with the spectral shape of a Gaussian (and therefore also the time shape), it might get quieter as it moves across the room, and longer, but will still "sound" the same.