Ari Ambrose’s Waiting (Steeplechase) is totally lacking in pretension. An exceptional example of mainstream modern jazz, the album features the tenorist in a classic hard-bop quintet with trumpeter Alex Norris, pianist Jon Cowherd, bassist Ugonna Okegwo and drummer Joe Strausser performing a program that mixes standards and Ambrose originals. Miles Davis’ “Milestones” (the bebop version on Savoy, from 1947), performed in the standard bop format, reveals the nature of the forthcoming music, which includes a lovely “Everything Happens to Me” along with swinging versions of “East of the Sun, “Without a Song” and “My Shining Hour.” Ambrose’s own compositions, “Sem,” “Quietly” and “Waiting,” with their sometimes open, airy quality, offer a more contemporary sounding contrast. The leader’s prodigious, machine-gunner articulation on the swingers and smooth melodicism on the slow tunes pairs up nicely with Norris’ elegant all-tempo lyricism. The rhythm section is solid, with Cowherd also serving as a third strong soloist. Whether or not it was planned, the soloists’ frequent practice of taking up the previous player’s last phrase in beginning their own solos grabs the attention and helps maintain continuity.