The fourth and final CD in Document's extensive Ida Cox series features the classic blues singer in a variety of settings: backed by her future husband Jesse Crump on eight selections from 1927; accompanied by a variety of mostly unknown players on a dozen numbers from 1928; joined by a trio (including trombonist Roy Palmer) on two 1929 sides; and, finally, assisted by five Count Basie sidemen (trumpeter Shad Collins, trombonist Dickie Wells, tenorman Buddy Tate, bassist Walter Page and drummer Jo Jones) and pianist James P. Johnson during her two songs at the 1938 Spirituals to Swing Concert. Unfortunately, Document did not put out a Vol. 5 to cover Cox's 1939-40 recordings (which were reissued by Affinity). Although none of these individual selections became that famous, she is heard in prime form throughout, and she is at her best during the duets with Crump. In fact, Cox is in such fine form during her 1938 concert appearance that it makes one wonder why she was not more active on records during the 1930s and '40s. The first two CDs in this series get the edge, but all four will be wanted by vintage blues fans.