Previously available as four albums -- two albums for each night -- that were reissued with no additions at the onset of the CD area, the Blackhawk concerts Miles performed in the Spring of 1961 are finally getting properly documented. This four-disc box set (also available as two, double-CD sets) not only remasters the material, but it presents the seven sets the quintet performed over this April weekend in their totality ... repeats and all. Thus, of the 29 tracks here, 13 of them are previously unreleased, and as such, this collection is much more reflective of the actual goings-on at the club. Though treats like a stretched-out "Autumn Leaves" are nearly worth the price of admission, it's clear that the cuts chosen for the initial releases of these dates were superior, as they spark with the vitality of a Miles club gig. Although Davis' reliance on standards and self-penned chestnuts certainly allowed him to loosen up while breaking in new tenor player Hank Mobley, a few of the tracks (like the shoulda-been-excited "Two Bass Hit") are played with a near-laziness. Nonetheless, the overall vibe for this weekend was high spirits and fiery performances and if the four original editions of this music are resting in your collection somewhere, you'd do well to round 'em off with this box.