Classifying the quirky personalities that feed the unique world of Virtuoso Piano Wonkdom – White loner physicist-types, obsessive packs of Asian graduate students, eccentric trustafarians ripped from the script of “The Royal Tenenbaums” – could make for an interesting program of psychological research. For those interested in making their own investigation, an annual migration of the species is currently under way to Mannes College of Music. The fourth International Keyboard Institute and Festival was launched Sunday by its esteemed founder, the pianist Jerome Rose, and continues through July 25.

As in festivals past, Mr. Rose plays host this summer to a quirky roster, including the Canadian virtuoso pianistcomposer Marc-Andre Hamelin (July 16) and Juilliard performance scholar David Dubal (July 19). But this year the festival celebrates Steinway’s 150th anniversary and therefore turns slightly more mainstream with the appearances of Her Majesty Alicia de Larrocha (in a master class on July 20) and the Beaux Arts Trio’s octogenarian founder Menahem Pressler (July 24).

To kick things off Sunday, Mr. Rose presented a piano-recital appreciation with a meaty solo menu of Schubert’s beloved G Major Sonata, D. 894, and Brahms’s early, more obscure, and youthfully rambunctious Third Sonata, in F minor, Op. 5. This was a piano concert for piano lovers, and Mr. Rose is one of the finest poets of the keyboard.

But what makes Mr. Rose so beloved in the piano world is his ability to perform music phenomenally well with the affectations of connoisseurship – he plays expertly for experts. Part and parcel of that, perhaps, is a certain lack of showmanship.That is what has always kept him on the edge of a major performing career, and that is what made Sunday’s concert so hard to connect with despite the ovations.

In the Schubert, a forlorn and often serene work, Mr. Rose’s signature effects appeared in the form of extremely even-voiced, soft-touch chords, patiently timed dotted rhythms, inhumanly long vocal lines, and supple rubatos. His orchestrational method of keyboard tonepainting rendered repetitive lefthand figures as the dark retorts of a cello section, while dancing righthand pirouettes the playful shimmers of a sweet violin band.

The playing was pristine – tonerich, beautifully contoured, often on the slow side with transparent color gradations at every deceptive minorkey landing. But it was playing for pianists and the hermetic band of elitist critics who love them, and I wanted more strangeness, more direct communication. The work was too much of a classical sculpture or epic poem, too distant, when it could have been more personal.

At its conclusion Mr. Rose blurred the overtones of an improvisational run of chromatic notes, the sort of novel turn I would have liked to see more of. By then, however, it was too late to be touched.

Mr. Rose’s way with Brahms was different, at least at the beginning. He attacked the opening gestures, flaunting clangorous punctuations before introducing a sharply staccatoed bass figure that drove home the first movement and the chordal tunes that make it sing. Singing became an obsession, however, in the slow second movement – in the melodies, there was too much beauty for beauty’s sake. And the great, gradual climax of joy made of grandly resonant pedal tones felt a bit too premeditated.

More honest was the jolly scherzo – here was young Hamburg Brahms, he of drinking games and prostitutes. But the dreamlike intermezzo and its deliberate fog left me cold. The free-wheeling Lisztian quality of the last powerfully played movement realized the work’s youthful, exaggerative qualities as well as possible, but – like much of the rest of the concert – its calibrated perfection was isolating.

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It’s often presumed – by audiences and critics – that a show full of faults is unpleasant and that a spotless performance is the most pleasurable. In fact, a spirited and skillful performance with a few flaws can be more instructive and consoling than a virtuosic display.

On Friday at Bargemusic, the veteran Russian pianist Alexander Slobodyanik performed a solo recital of Chopin, Brahms, and Prokofiev. Mr. Slobodyanik once performed under such conductors as Leonard Bernstein and Kiril Kondrashin, and did so with spotless technical precision and dramatic grandeur. These days, Mr. Slobodyanik must call forth greater concentration and dedication for every note, but he renders timeless, emotionally rich music, as a mature artist should.

Famous in piano circles for his thunderous downbeats and thick, expressive melodies, Mr. Slobodyanik has apparently also lost some of his luster. He missed more than a few notes in Chopin’s Etude No. 12, Op. 10, and his hands shook. But his soft, powerful touch kept the left-hand motive undulating as the right remained fluid and rambunctious. He triumphed over himself in the end – which was heartwarming.

Mr. Slobodyanik added a layer of muscle and haze of self-consciousness to Chopin’s Op. 25 Etudes, Nos. 1-12 – music that often seems too prettified. In the second etude, the runs were balletic but rambling. Mr. Slobodyanik’s hands flopped about in the grace-note spotted third etude, and choppy offbeats punctuated the fourth. But even though the fifth etude came off too sloppily jazz-like, the foggy, soft opening of the 11th etude and the chromatic descents and contrary motion runs of the last produced such furious attacks that the small technical errors faded in importance.

Brahms’s Walzer, Op. 39, didn’t fare as well. Mr. Slobodyanik used sheet music and appeared unprepared. He imparted hearty Russian flavor to strong Viennese jump-off rhythms and tender, fatherly melodies. But even easy Brahms isn’t easy. These waltzes sound simple, but inside their strains of melody live as many important notes as those that render Brahms’s piano concertos treacherous. More important, the pieces hinge on those hidden notes.

Mr. Slobodyanik had clearly practiced Prokofiev’s Sonata No. 7, Op. 83 – the composer’s most manic and efficiently sarcastic work in the genre. The angular piece began tensely, and became even more so; the second slow movement was thick but nostalgic and played lyrically, on the quicker side. But the performance became timeless in the last movement, precipitato.

It’s not exaggerating to call Mr. Slobodyanik’s rendition one of the most exciting I’ve ever heard. As the perpetual motion phrases progressed, the obsessive motives only got crazier, heavier, louder, more militarist. Was this a trip into Stalin’s mind? Was Mr. Slobodyanik trying to convince us that Russian pianists are as crazy as they’d all like us to believe?

The performance, like the concert, had high and low moments, but it had human drama. Mr. Slobodyanik is the real thing, and though the act gets harder with age, his commitment to performance and to works like the Prokofiev Seventh are still enough to power him through.