Meson mass spectrum and OPE: matching to the large-N_c QCD

The relations between masses and decay constants of variety of meson resonances in the energy range 0--3 GeV are verified from the string-like, linear mass spectrum for vector, axial-vector, scalar and pseudoscalar mesons with a universal slope. The way to match the universality with the Operator Product Expansion (OPE) is proposed. The necessity of small deviations from linearity in parameterization of the meson mass spectrum and their decay constants is proven from matching to OPE.