  We consider general properties of groups of interacting oscillators, for
which the natural frequencies are not in resonance. Such groups interact via
non-oscillating collective variables like the amplitudes of the order
parameters defined for each group. We treat the phase dynamics of the groups
using the Ott-Antonsen ansatz and reduce it to a system of coupled equations
for the order parameters. We describe different regimes of co-synchrony in the
groups. For a large number of groups, heteroclinic cycles, corresponding to a
sequental synchronous activity of groups, and chaotic states, where the order
parameters oscillate irregularly, are possible.
