The maximum transverse magnetoelectric (ME) voltage coefficient alpha(E31) similar to 235 mV/cm Oe and maximum longitudinal ME voltage coefficient alpha(E33) similar to 148 mV/cm Oe were obtained in co-fired PbZr0.52Ti0.48O3-Co0.6Zn0.4Mn0.3Fe1.7O4 (PZT-CZFMO) bilayer composite (optimum thickness ratio t(PZT)/t(CZFMO) similar to 1:3) at H = 700 Oe with an applied ac magnetic field of frequency = 1 kHz. Interestingly, at the lowest frequency of measurement f = 100 Hz, a giant value of alpha(E31) similar to 16.9 V/cm Oe was observed for this bilayer system that is orders of magnitude higher than the reported alpha(E) values (similar to 200-300 mV/cm Oe) for PZT-CFO composite structures at low frequencies. Better magneto-mechanical coupling resulting from the simultaneous substitution of both Mn and Zn in CFO along with the optimum thickness ratio of two layers must be the cause of substantial ME coupling in the PZT-CZFMO bilayer system. In addition, the dielectric constant spectra of bilayer revealed very high thickness resonance frequency similar to 85 MHz and band width similar to 14 MHz. (C) 2014 Elsevier Ltd. All rights reserved.