The Large-Aperture Experiment to Detect the Dark Ages (LEDA) is designed to detect the spectrum of the 21 cm Hydrogen line from the Intergalactic Medium (IGM) at redshifts of 15–30, when the Universe was just ~1% of its present age. It is located at the Long Wavelength Array site, adjacent to the Very Large Array. LEDA principally comprises a "large-N" array correlator, calibration & imaging system, and instrumentation for measurement of calibrated total-power. These systems will use the station 1 of the Long Wavelength Array as an aperture. LEDA will feature array-based calibration to improve the accuracy of foreground subtraction from the total-power signal.