  We review and extend the model derived in Phys. Rev. D83 016007 (2011) to
address the dynamics of the low-lying even parity meson resonances. This model
is based on a coupled channels spin-flavor extension of the chiral
Weinberg-Tomozawa Lagrangian. This interaction is then used to study the S-wave
meson-meson scattering involving members not only of the \pi-octet, but also of
the \rho-nonet. In this work, we study in detail the structure of the SU(6)
symmetry breaking contact terms that respect (or softly break) chiral symmetry.
We derive the most general local (without involving derivatives) terms
consistent with the chiral symmetry breaking pattern of QCD. After introducing
sensible simplifications to reduce the large number of possible operators, we
carry out a phenomenological discussion of the effects of these terms. We show
how the inclusion of these pieces leads to an improvement of the description of
J^P = 2^+ sector, without spoiling the main features of the predictions
obtained in the original model in the J^P = 0^+ and J^P = 1^+ sectors. In
particular, we find a significantly better description of the
I^G(J^{PC})=0^+(2^{++}), 1^-(2^{++}) and the I(J^{P})=\frac{1}{2}(2^{+})
sectors, which correspond to the f_2(1270), a_2(1320) and K^*_2(1430) quantum
numbers, respectively.
