  The frequency dependence of normal pulsar radio emission is typically
observed to be a power law, with some indications of a flattening or turnover
at low frequencies ($<100$ MHz). The spectrum of the Crab pulsar's giant pulse
emission has not been examined as closely. We conducted simultaneous wideband
observations of the Crab pulsar, with the Parkes radio telescope and the
Murchison Widefield Array, to study the spectral behaviour of its giant pulses.
Our analysis shows that the mean spectral index of Crab giant pulses flattens
at low frequencies, from $-2.6\pm0.5$ between the Parkes bands, to $-0.7\pm1.4$
between the lowest MWA subbands.
