A novel flat-flat resonator consisting of two crystals (Nd:YAG + Nd:YVO 4 ) is established for power scaling in a diode-end-pumped solid-state laser. We systematically compare laser characteristics between multi-segmented (Nd:YAG + Nd:YVO 4 ) and conventional composite (Nd:YAG + Nd:YAG) crystals to demonstrate the feasibility of spectral line matching for output power scale-up in end-pumped lasers. A maximum continuous-wave output power of 79.2 W is reported at 1064 nm, with M 2 x = 4.82, M 2 y = 5.48, and a pumping power of 136 W in the multi-segmented crystals (Nd:YAG + Nd:YVO 4 ). Compared to conventional composite crystals (Nd:YAG + Nd:YAG), the optical-optical conversion efficiency of multi-segmented crystals (Nd:YAG + Nd:YVO 4 ) from 808 nm to 1064 nm is enhanced from 30% to 58.8%, while the laser output sensitivity as affected by the diode-laser temperature is reduced from 55% to 9%.