The six tracks on Duke Ellington's Conny Plank Session include heretofore unreleased recordings made at Cologne's Rhenus Studio in 1970. Grönland Records discovered them while investigating reels in the producer/engineer's estate. While they do answer some long-held questions, others remain unclear (exact personnel, for instance). According to Henrik von Holtum's liner essay, the actual date is unclear as well. While they are marked "April," many in the obsessive, labyrinthine world of Ellingtonia claim they were made in July while the band was touring Europe. How the session came to be is also in some dispute: Did Ellington rent the studio for a recording stockpile session? Or was the band rehearsing at Rhenus when Plank asked if he could record them? The quality of the music and the presentation assert that it makes little difference to any but the most fanatical of historians. There are three takes of the hard-swinging "Alerado" and three of the more adventurous "Afrique." On the former, a forceful walking bass introduces the front-line horns before Wild Bill Davidson's organ emerges to dialogue with the section. There are excellent solos by him, Cat Anderson on trumpet, and Norris Turney on flute. Plank pans left and right between soloists and orchestra, offering a full aural portrait of the room and a truly live feel. The final take is much slower, more interior and reflective -- Davidson's organ is nowhere near as prominent, but the swing quotient is still high. The first take of "Afrique" is introduced by Rufus Jones' rumbling drum vamp (the tune's central feature that would remain on its finished version on The Afro-Eurasian Eclipse in 1971) with the horns staggered tonally in a slightly angular, Eastern-tinged blues. Plank's balance captures the sound of the band as they hear one another -- though the tune is very much in process. At over seven minutes, there is still a lot of repetition and in the next two takes, Ellington trims the fat and ups the tempo. On the second take, his piano comes slicing into the mix, isolated by Plank for maximum effect. Each tonal variance in the horn section is captured despite the fact that this is a demo, and the bass solo really comes popping through the middle. In the final take, an unidentified female vocalist plays the role of yet another soloist, adding more of a vanguard feel as the track bleeds to the edges. Ellington's piano guides the number through various transitions as Victor Gaskin's bass roars to the front with the drums and a pair of bluesy saxophone solos. The Conny Plank Session will likely be of more interest to Ellington's fans than Plank's (who are usually more tuned into his rock work). Nonetheless, this is solid proof of the great bandleader's expression of admiration for the engineer's work. And the music, captured so late in Ellington's life, is an intimate, fascinating slice of creative history.