It’s tempting to view songbook excursions in purely binary terms—assuming any re-litigation of a well-trod canon to be either an exercise in rote reverence or in cheeky desecration. A pair of new albums—both of them ostensibly jazz, or at the very least jazz-adjacent—have it both ways, exploring the contours of familiar songs and keeping the material both formally and spiritually intact, yet still allowing it to live and breathe in a whole new context.

Released for the great composer and pianist’s centennial birthday, MAST’s Thelonious Sphere Monk chops, screws, dissects, and bedazzles 16 Monk tunes—and just when you find yourself bracing for the next irresistible curveball, the album throws you a straight one, just to remind you of the skewed and enchanted beauty found in the originals. MAST is the project of L.A. guitarist and producer Tim Conley, who kicks these beloved songs down a staircase where they hit every electronic bleep and bloop along the way, but land without bruise or blemish: There’s not a song here that doesn’t pass through the filter of MAST’s colorful imagination, and not a song that’s anything less than instantly recognizable in its ravishing melody and off-kilter beauty. It’s an album where live jazz and trippy studio effects happily coexist: “Evidence” throbs with low end rumble and lurches through funhouse beats and samples before a full horn section comes in; the song cuts back and forth between trumpet and sax like they’re turntable samples, yet there’s visceral thrill to the horn players’ blazing fury and lively improvisation. It’s an album of thrilling transitions, too: As “Evidence” collapses into skittering beats, it melts seamlessly into the pulsing upright bass of “Bemsha Swing,” setting the stage for the clear melodicism of Conley’s electric guitar solo. Just as pianist Robert Glasper kept his Miles Davis tribute largely trumpet-free, Conley largely keeps pianos out of the spotlight here, highlighting the breadth and depth of his compositions rather than the rickety genius of his soloing—yet when Brian Marsella shows up to tickle the ivories on a fairly straight version of “Ask Me Now,” he connects the dots between Monk’s childlike whimsy and his roadhouse roots, proving that Monk contained multitudes. Elsewhere, Conley tests the resilience of these Monk tunes by letting them collide with more modern forms and tropes: A wobbly take on “Oska T” interpolates loose piano with a boom-bap drum beat, drawing a straight line from Monk’s wooziness to the punch-drunk beats of J Dilla. “Blue Monk” is done as a rattling headphone symphony, the melody carried entirely by the cavernous bass. An album-opening take on “Misterioso” allows Monk’s tune to drift in on a bed of synth ambiance and resounding gongs. “Epistrophy,” where a full horn section plays hot blues across breakneck drum ‘n’ bass, feels like the most maniacal thing here, until a late-album take on “Trinkle Tinkle” creates trance music almost entirely through the cling and clatter of percussion instruments. But no matter how much these songs are dressed up or dressed down, MAST retains their core appeal—their winking humor, their disoriented physicality, and most of all Monk’s melodicism, as unabashedly tuneful and romantic as Ornette’s or Billy Strayhorn’s. Only Monk himself composed richer, more imaginative Monk albums, and the triumph here is how Conley and his cohorts carry the torch of the composer’s own relentless reinvention—how he was always able to make these songs sound fresh again, no matter how many times he played them.

More austere but no less interested in songbook excavation as a catalyst for creative expression, Brad Mehldau’s solo piano album After Bach presents five Bach pieces—played with finesse and with passion—each followed by Mehdau’s reimagining. His ambitions are clear from the outset, as he spends just over a minute reciting the melody of “Prelude No. 3 in C# Major” before launching into his “Rondo” variant—the latter boasting an immediately recognizable melody but a looser, more languid pacing, the space between the notes transforming its mood from contemplative to gently swinging. Mehdau’s solo piano albums have long blurred the lines between classical and jazz (see Elegiac Cycles) and boasted knotty conceptual thinking (see 10 Years Solo Live), so it’s no surprise that After Bach offers something a bit more refined than a familiar “head” opening up to riffing and improvisation: Each of the “After Bach” pieces offers a thoughtful rewiring of the Bach original, with a “Flux” reading turning the “Prelude No. 10 in E Minor” inside out and a monumental “Ostinato” version of “Fugue No. 16 in G Minor” spending a full 12 minutes moving from expressionistic ambiance into a symphonic swell, gradually winding its way back down through classical precision and jazz abstraction. Mehldau presents a manifesto on timing and empty space, and as with the MAST album, he reinvents an enduring songbook without ever obscuring its resonant melodies. Most impressive of all is how Mehldau’s spritely playing and intelligent constructions make the album a natural and engaging listen, never feeling overly studious even in its repetition of material.

These two albums sound little alike, but make for accidentally illuminating companion pieces: Taken together, they lay out a continuum of classical music morphing into jazz, jazz evolving further into electronica; and, they both find progression in tradition, making a case for old songs as catalysts for new ideas.