  We have recently extended the scalar-pseudoscalar sector of a generalized NJL
Lagrangian that includes all NLO non derivative interactions in Nc counting
(including explicit symmetry breaking ones) in order to incorporate the spin 1
mesons in the low-lying ground state of QCD [1]. Upon bosonization, the well
known mixing of the scalar-vector and of the pseudoscalar- axial-vector fields
occurs in the quadratic part of the Lagrangian. We show that a linearized
diagonalization of these terms can be effected in a completely general way
without compromising the underlying symmetries of the Lagrangian [2]. The
resulting spin 1 mass spectra evidence a relation involving only the vector and
axial-vector meson masses and the constituent quark masses. We discuss the
dominant role of this relation in the fits and we show that the model may be
fitted to accommodate to a very good accuracy the 4 low-lying meson spectra.
