The Frode Gjerstad Trio started up in 1999 with Paal Nilssen-Love and bassist Øyvind Storesund and nearly 20 years later is still going strong, with Jon Rune Strøm now holding the bass chair. The trio is augmented here by guest Steve Swell joining them for a session recorded in performance in September 2017 at The Bop Stop in Cleveland Ohio and released by the Clean Feed label.

Playfully, the titles of the four tracks are "Bop Stop," "Stop Bop," "Pop Bop" and "Post Stop." Improvisation takes front row center, and these musicians can dish it out expertly in the nearly one-hour set of music. The recorded sound is pristine with the texture and clarity of a studio set up. This allows one to appreciate all the subtleties of the music, from the growls of sax and trombone and the flurry of brushwork from Nilssen-Love and the throbbing bass pulse, as in the epic opening track "Bop Stop".

Flowing drums rolls open the second track, in what ends up being a rolling and tumbling piece, starting with just a drums+reeds duo, augmented and supported by Swell's swanky trombone blasts. Bone and bass soon engage each other over the relentless power surge of Nilssen-Love drums, which eventually gives was to a percussive and expressive sax foray over an industrial-strength bass and drums carpet of sound. Swell's trombone comes in again, but the linking thread throughout is the ongoing inspired, driven drumming that doesn't let up until the piece's gradual resolution, after bassist Strøm gets more than a few words in edgewise.

The heat is turned down somewhat in "Pop Bop" as the timbral aspects of sax and trombone are fore-grounded, showing these musicians' control and imaginative use of extended techniques like split tones, wind patterns, pedal tones, use of mutes, smears, and many other colorful effects that make your average guitarists' pedal board seem like a dinky box of crayons.

The final track starts much like the previous one developed into, but takes the musical argument to a lithe conclusion, as all four musicians engage in some meaningful and articulate conversation.