For all the popularity of Mozart's five Violin Concertos, his two true masterpieces in the genre are the Concertone - a Triple Concerto for two Violins and Oboe in all but name, at times turning into a Quadruple Concerto with the addition of an obligato cello - and the Sinfonia Concertante for Violin and Viola. The Concertone may be an early work of Mozart, written when he was 17 (all is relative of course - like Schubert's, all Mozart works are "early", and the Sinfonia Concertante, considered the "mature" work, was written at 22), and his first real Concerto (all the previous ones had been arrangements of Sonata movements from other composers), and it is still marked by the influence of the galant style in its middle movement and Finale, but it also teems with irresistible enthusiasm and wonderful melodies and smacks of the opera in its boisterous opening one.
These recordings by the Smithsonian Chamber Orchestra, with Jaap Schröder leading and playing first violin, made in 1986, are great versions on period instruments, likely to please even listeners adverse to historically-informed Performances (HIP), because there is nothing radical about them, they are played in a classic manner, lively and spirited in the outer movements (with the exception however of the Concertone's Minuetto-Finale, see further), and true to Mozart's "Andantino grazioso" in the middle movement of the Concertone. Anti HIPsters might object to their taking the middle movement of Sinfonia Concertante at a flowing pace, closer to the "Andante" written by Mozart than to the romanticized and solemn Adagio many (including, to an extent, Harnoncourt, Mozart: Sinfonia Concertante, Violin Concerto, Kremer, Kashkashian) turn it into, but not only is it truer to Mozart's indication, I find that Schröder and McDonald show a touching restraint there, with neither flaunted pathos nor the emotional turbulence of Heifetz (a great reading, at an even brisker tempo, Double Concerto), eliciting instead a mood of touching tenderness. There is the touch of acidity associated to period instruments but great timbral character from the strings, and oboes and horns in Sinfonia Concertante are covered just a little too much in the tutti in the first movement, but marvellously present in the finale. The two soloists, Jaap Schröder and Marilyn McDonald (the booklet - no liner notes - of this budget reissue attribute only the "violine/violin/violon/violino" to her as well as to Schröder, but in Sinfonia Concertante it is evidently the viola), play and blend well, McDonald's viola tone isn't big, but it is creamy.
The first movement of the Concertone teems with youthful jubilation, the sonic perspective of the orchestra is perfect, with the oboes and horns never covered by the strings and the strings never over-resonant and excessively symphonic, underlining the Serenade nature of the music. Schröder and McDonald blend beautifully, making them almost indistinguishable, and oboist Stephen Hammer must be lauded for his marvellous timbral character. Their take on Mozart's "Andantino grazioso" is exactly that: andantino and gracious, very catholic in its choice of tempo (it is virtually the same as Oistrakh's, Mozart: Sinfonia Concertante, KV 364 in E Flat Major, Concertone KV 190 in C Major, Adagio KV 261, Rondo KV 269), at times vaguely languorous, but with sombre hues when comes the passage in minor mode at 5:15. I would take exception only with their tempo in the Menuetto-Finale. There is a puzzling contradiction in Mozart's indications there: "Tempo di Menuetto", and you easily associate that with a somewhat pedestrian pacing - the menuetto was an elegant, aristocratic dance after all, not a rock-and-roll - but then Mozart adds "Vivace". A vivacious Menuetto, then. Clearly, Schröder favors the elegant aristocratic and vaguely stately dance. I find versions that take Mozart's "Vivace" at face value (as, recently, Yakov Kreizberg with Julia Fischer, Mozart: Sinfonia Concertante [Hybrid SACD]) more convincing, and certainly more exciting.
But this very elegance of Schröder here is an additional factor likely to please even those adverse to the style associated to period instrument playing.