  We study the spectral properties of and spectral-crossovers between different
random matrix ensembles (Poissonian, GOE, GUE) in correlated spin-chain
systems, in the presence of random magnetic fields, and the scalar
spin-chirality term, competing with the usual isotropic and time-reversal
invariant Heisenberg term. We have investigated these crossovers in the context
of the level-spacing distribution and the level-spacing ratio distribution. We
use random matrix theory (RMT) analytical results to fit the observed
Poissonian-to-GOE and GOE-to-GUE crossovers, and examine the relationship
between the RMT crossover parameter {\lambda} and scaled physical parameters of
the spin-chain systems in terms of a scaling exponent. We find that the
crossover behavior exhibits universality, in the sense that it becomes
independent of lattice size in the large Hamiltonian matrix dimension limit.
