As previously mentioned, I had listened to a grand total of three jazz albums before setting out on this expedition. We've already encountered Kind of Blue; one of the other two was Side by Side—Side by Side was mostly a Johnny Hodges album, but they stamped his better-known bandleader Ellington's mug on the cover, presumably to juice the sales.

I bring all of this up because this week's album features some of the same suspects: Ellington has gathered together his big band (Hodges included), but they're not alone: Count Basie—another big band luminary—is on set with his crew, and out to wage Big Band "Battle Royal" (sic)! The stereo mix is intended to capture the conflict: Basie's group is heard on left channel, while Ellington's is on the right.¹ To my undiscerning ear, the result sounds as cooperative as it does antagonistic, but that doesn't stop it from being a blast through and through. At peak moments, the brass can get a little screechy; I don't think it's ever over the top but my wife is not on board with it. (E.g., listen to the climax of Battle Royal—it's on the verge of cacophony, but I think it remains on the "impassioned finale" side of the line.)

I've bandied about "big band" above with any proper explanation, so I suppose I ought to fill in some of those details: big band is exactly what it sounds like—a musical ensemble for jazz that consists of at least ten (and often 17 or more) musicians (usually divided into saxophones, trumpets, trombones, and rhythm). Compared to earlier jazz ensembles (which typically comprised 4–5 musicians), big bands were obviously larger, but also had a greater focus on written compositions (owing to the increased difficulty of coordinating solos across a much bigger group). Big bands reached peak popularity in the late 1930s/early 1940s alongside "swing," the subgenre of jazz they usually played. Swing was very popular at dance halls; as you might guess from the name, it features a "swinging" rhythm (usually by accenting the second and fourth beats). Both Duke Ellington and Count Basie were both highly regarded big band leaders who shaped the development of swing (Ellington in particular was also a prolific composer and arranger).

tl;dr:

Big band

Jazz group of at least ten musicians (probably more).

Swing

Subgenre of jazz with a strong emphasis on a "swinging" rhythm; frequently played at dance halls.

Favourite track: Wild Man (aka Wild Man Moore)²