The El País expert sudoku from May 22, 2024. NOTE: Sound experiment!

[@DavidShatz-hw6jl]

Finding the 3 in C5 followed by a multitude of blocks throughout the grid successfully negotiated the solve! A good deal of “healthy” cognition unraveled this grid! Good luck with a busy day of planned activities!

[@AnonimityAssured]

Ah, the old faithful returns. No surprises, but a good speed run (31 = row 3 column 1): 31, 51, 27, 78, 83, 22, 85, 87, 49, 13, 24 (hidden pair in box), 89 (hidden DCE), 86, 25 (using the pair again), 33, 23, 95, 26, 28, 36, 45, 41, 77, 94, 35, 34, 65, 46, 15, 16, 76, 74, 75, 64, 55, 42, 37, 47, 52, 93, 63, 43, 48, 61, 59, 98, 72, 71, 12, 11, 92, 91, 79, 99, 68, 69, 38, 39.