The Ravel came first, which was a bold move in itself — but a canny one, too, in that it allowed the pair to open with a movement that played eerily well to their respective strengths. Steeves' limpid, gracefully unhurried opening was just about ideal. So too was Dahn's response — to the same theme, but now with a tension in it imparted partly by the now-restless piano part, partly by the innate character of her own sound. It's bright without being at all coarse, smooth, very powerful, and under exceptional control. All of which made for a performance that avoided all of the traps: elegant, but not effete; powerful, but not rough; serene, but not conventionally "romantic" at all. It caught the mood of that strange movement — so vivid and so remote — very well.

The succeeding "Blues" is one of those perennial interpretive problems: do you treat it seriously as "the Blues," or as "Ravel stylizing the Blues" (at the remove of one large ocean and really bad recorded sound)? Both can work, though in my experience the second is safer — "coolly ironic" is just so much easier to do well than "dirtily authentic," especially if you've spent the bulk of your recent waking hours in a practice room. For Dahn, "cool irony" was the obvious choice, but she seemed to vacillate a little early in the movement, as though she were unsure whether to go earthy or elevated. By the climax, frankly, it made no difference; she was exuberantly both, with that intense sound communicating Dionysian abandon even as her tight control seemed to belie it. Then the moto perpetuo finale — brilliant and nimble in both parts, though not ideally balanced (Dahn can hold her own with her partner in almost any other sort of texture, but in fast spiccato the "chiff" of the bow's attack sometimes projected better than the pitch did).

The "Kreutzer" Sonata, which ended the program, of course makes rather different demands, so it was a little surprising how well basically the same performance style seemed to meet them. Dahn's steely steadiness was even more remarkable here than in the Ravel. She is a graceful and natural musician, though not an extraordinarily imaginative one; but she has two assets that many much better-known violinists ought to envy. First, that amazing sound, very keen but not harsh, and well capable of standing up to a concert grand with the lid open. (And bravo to Steeves, by the way, for having the lid up — every other duo recital I've heard at Old First has suffered from muffled piano sound because someone had "balance issues" and put the lid on the short stick.) Second, a left hand — or rather a combination of left hand and ear — of remarkable accuracy. Intonation as pure as hers is a pretty rare thing, even at the top levels; you could almost recalibrate your tuner by it.

Those two qualities meant a "Kreutzer" in which you could hear absolutely everything, and also had perfect confidence that the players knew where they were going at all times. That kind of calculation can be a little alarming, especially when it seems to the ear (as it usually did here) entirely natural and even spontaneous. Close your eyes and you hear splendid, sweet little nuances everywhere; open them, and the first thing that comes into your head is "My God, they never look at one another at all!" (And, right after that, "How long did they have to rehearse that exquisite little rubato before they got it to this point? And if you heard them play the same piece again, would it be exactly the same?" I think, maybe, yes.)

Mind you, keeping your mind temporarily off issues of calculation may not be too high a price for some to pay for a performance like that one. Dahn playing at full strength is formidable (and she played about the tightest rhythms I've ever heard in the finale), while Steeves was scarcely less good, articulate and powerful without banging. All the same, I felt rather as I did after hearing the old Tokyo Quartet replicate to the microsecond, in a live performance, a very delicate rubato they'd done on a recording I already knew. It's a great achievement, but a cold one.

Between the two big works came two others. Smetana's From My Homeland was brilliant. I am not qualified to judge the performance's Czechness, but it was saucy and soulful and supremely confident. And Kelly-Marie Murphy's Dance Me to your Beauty with a Burning Violin, written for Duo Concertante, caught everything essential about the two players and their partnership. For Dahn there were furious cadenzas; for Steeves, tinkling arabesques at the top of the keyboard; for both (most tellingly), two long sections in a fast quintuple meter with intricately interlocking rhythms that both players nailed like competitive archers putting the arrow nonchalantly through the bullseye the fiftieth time in a row. I think Kelly-Marie Murphy knows these two musicians very well. Call it a double portrait.