Hidden in plain sight: a double-lined white dwarf binary 26 pc away and a distant cousin

We present high-resolution spectroscopy of two nearby white dwarfs with inconsistent spectroscopic and parallax distances. The first one, PG 1632+177, is a 13th magnitude dwarf only 25.6 pc away. Previous observations failed to detect any radial velocity changes in this star. Here, we show that 1632+177 2.05 d period double-lined binary (SB2) containing low-mass He-core more-massive, likely CO-core companion. After L 870-2, becomes the second closest SB2 currently known. Our target, WD 1534+503, also an system orbital 0.71 d. For each system, constrain atmospheric parameters both components through composite model-atmosphere analysis. new set NLTE synthetic spectra appropriate for modeling cool dwarfs, effects core H$\alpha$ line increase decreasing effective temperature. discuss mass distribution eclipsing double constraints, demonstrate observed population consistent predicted from synthesis models. latter predict more massive CO + binaries at short ($<1$ d) periods, as well several day periods; such systems are still waiting be discovered large numbers.