A violin, a piano. That’s plenty.

Frank Almond and a Stradivarius, William Wolfram and a Steinway.

Almond and Wolfram are old Juilliard pals, former touring recital partners and frequent recording collaborators. They can pretty much read each other’s minds. They are monster players with a taste for especially challenging repertoire.

Monday evening, they took on Schumann’s Opus 120 Sonata, a work fraught with peril. The violin lines hang down amid the dense piano part. Nothing lies very well on the violin. Phrases often end with odd gestures. Melodies thrust and feint as they sprawl on and on. This sonata can turn to mud in the wrong hands, and it’s easy to get lost conceptually.

Almond and Wolfram had thought it through, from the startling bite of opening chords ripping across all four violin strings to the music-box delicacy and simplicity of the first half of the third movement and through the finale. The players made gripping and subtle drama of this sonata, and nowhere more than in that third movement. That sweet little theme grew ever more expansive, as if gaze and reach were turning from a single wild flower to the whole horizon. And then suddenly, shockingly, the alarm of those ripping chords from the outset burned it all down.

Almond plays the Lipinski Stradivarius, an instrument capable of both remarkable sonic heft and the utmost refinement. The two are not mutually exclusive in Almond’s hands. The Strad sang out over the piano line, and Wolfram didn’t have to hold back. The two parsed out those fitful melodies and made them easy to grasp. Clear rhythms, sure impetus and exquisite balance revealed the fascinating interaction of the parts. Schumann wove murmuring echoes of the violin lines into the piano accompaniment, and Wolfram let us hear them. They trail along like little tremors, aftershocks of the violin line, and each one was a miracle Monday night — and crystal clear in the marvelous acoustic of Schwan Concert Hall at Wisconsin Lutheran College.

Julius Röntgen’s (1855-1932) Sonata No. 2, Opus 20, was a revelation. This concert was also the preview party for Life of a Violin, the forthcoming Avie disc celebrating the Lipinski Strad. The connection: Röntgen’s son once owned the violin. The German composer, who worked mainly in Amsterdam, was a great friend and protege of Brahms, and you can hear the influence in this sonata.

Röntgen was a Romantic after the Romantic era had expired, but this is a superb piece. The composer had a way with the soaring lyric line. So does Almond; composer and violinist bathed each other in flattering light. Röntgen crafted a nifty fake folk dance in the second movement and nifty little folk song for the finale. But they don’t go quite where you expect them to go; this is not pro forma music and surprises abound. Both of those ditties transformed ever so slyly into sophisticated city music. Once Röntgen presents his themes, he deftly breaks them into call and response elements, which evolve as the conversation goes on. Almond and Wolfram understood this exactly and made warm and witty dialogue of the music.

They cast a sunny spell with Brahms’ (relatively) straightforward Sonata in A, Opus 100, Brahms at his most charming. Rich warm harmonies stay bright, unshaded the passing clouds that typically complicate the mood of his music. His rhythmic complications, usually tense with the pull of duple against triple, here generate lively percolation. Almond and Wolfram joined in the spirit of it first by maintaining ravishing sound throughout and second by projecting an irresistible, ingenuous sense of delight in the doing. This music is not frivolous; it has weight. The trick is to hold that weight effortlessly yet securely, and these players did that.

Wolfram is a big, assertive guy with a special gift for big, assertive music. Which explains why he’s made something of a specialty of virtuoso transcriptions/fantasies of Romantic operas. Such pieces, rarely played today, were all the rage from about 1850-1900. Monday, Wolfram played Liszt’s shorter treatment (he made two) of the “Pilgrim’s Chorus” from Wagner’s Tannhäuser. Ever so patiently, Wolfram built this thing to a jaw-dropping roar, then ever so patiently allowed it to fade away. Astounding. That’s the point.

As an encore, they played the Grand Adagio from Glazunov’s ballet music for Raymonda. It floated through the hall like so much atomized Chanel No. 5. That’s the point.

Next up for Frankly Music: Mendelssohn, Dvorák, Haydn; The Frankly Music Chamber Orchestra; 7 p.m. Monday, May 13, Wisconsin Lutheran College.