Truman Osborn Angell (/ˈeɪndʒəl/ "angel"; June 5, 1810 – October 16, 1887) was an American architect who served many years as the official architect of the Church of Jesus Christ of Latter-day Saints (LDS Church). The brother-in-law of Brigham Young, he was a member of the vanguard company of Mormon pioneers that entered the Salt Lake Valley on July 24, 1847. He designed the Salt Lake Temple, the Lion House, the Beehive House, the Utah Territorial Statehouse, the St. George Utah Temple, and other public buildings. Angell's modifications to the Salt Lake Tabernacle are credited with perfecting the acoustics for which the building is famous.