A few months before the Great Depression in 1929, New York’s OKeh record label held a multiartist field recording session in Richmond that led to more than two dozen 78-rpm releases by area singers and musicians. We still don’t know exactly where this interracial talent show happened — restrictive Virginia laws concerning race mixing ensured that the endeavor was hush-hush — but OKeh’s engineers managed to capture a diverse array of sounds: old-time country music (Roanoke Jug Band, pictured, the Buck Mountain Band), white gospel (Bela Lam, Otis and Tom Mote), “hot” jazz (Bubblin’ Over 5), black religious quartets (Monarch Jazz Quartet, Sparkling Four), blues (Blues Birdhead), even a Hawaiian string band (Tubize Hawaiians) from Hopewell. While no popular hits ensued, the 1929 OKeh sessions left us an invaluable snapshot of Virginia sounds at a pivotal point in music history — charting changing national trends along with timeworn regional traditions. Good luck finding any of those original 78s; thankfully, today’s listeners can hear the OKeh sessions on an excellent CD reissue called “Virginia Roots.”