Etcetera: Blues reissues are flooding the market with music that’s potent and varied. King of the Delta Blues reaches back to the primordial country style of the Deep South, as recorded around 1930 by Charlie Patton, a Mississippi singer-guitarist who profoundly influenced such blues greats as Robert Johnson and Howlin’ Wolf. Patton’s coarse vocals and fleet finger-picking transformed an essentially low-key music into something intensely personal. A- …Washboard Sam?s 1940s recordings on Rockin’ My Blues Away show how the blues moved north to the big city. Although his instrument — the washboard — and many of his lyrics reflect his rural Arkansas roots, Washboard Sam (né Robert Brown) had the silvery voice of an uptown sharpie. These songs can be repetitious, but the buoyant energy of his performances more than compensates. B+ …Jimmy Yancey sounds like a boogie-woogie pianist at half speed on Chicago Piano Volume One — and that’s not a put-down. Yancey, who recorded these elegant, luxurious tunes in 1951, a few weeks before his death, produced melancholy rhythms with his left hand and sweet riffs and arpeggios with his right. The combination of the two is breathtaking. A