  The propagation of a quasi-harmonic electromagnetic wave in a bulk hyperbolic
dielectric metamaterial is considered. If the group velocities dispersion is
not taken into account, then wave propagation can be described either by the
hyperbolic nonlinear Schrodinger equation or by the hyperbolic Manakov
equations. It is shown that the region in the space of wave vectors in which
the modulation instability of a spatially homogeneous wave is possible is not
limited, in contrast to the case of ordinary media.
