Rudolf Serkin's musical relationship with his father-in-law, Adolf Busch, is documented three recent releases in which Busch figures variously as violinist, conductor and composer. Because of this variety, the three disc constitute gesture in the year marketing the 25th anniversary of Busch's death.

Both Adolf Busch and his older brother, the illustrious conductor Fritz Busch, died when they were barely past 60, both having distinguished themselves before they were 20. Adolf Busch found his famous string quartet (with younger brother Hermann as cellist) in 1919, his 28th year; in the 1930s he organized the Busch Chamber Players, specially to perform and record the "brandenburg" Concertos and orchestral suites of Bach (without "original instruments" in those days). Serkin, of course, performed with both of those ensembles, as well as with Busch alone in sonatas of violin and piano and as a member of a trio with Adolf and Hermann Busch.

On Turnabout THS-6558, Serkin is heard with the Busch Chamber Players in Mozart's Piano Concerto No. 14 in E-flat (K. 449), and on THS-65061, his recording of the Brahms Piano Quintet in F minor (Op.-34) with the Busch Quartet is reissued. Both performances, engraved on 78s in October 1938, are alive with the intimacy and spontaneity that illumine the most satisying chamber music presentations. The Concerto is given in what is very much a chamber-music frame, which suits its particular character very well indeed.

Curiously, Serkin was to remake both works with Alexander Schneider, who was second violin in the Budapest Quartet, in the current Columbia version of the Brahms (MS-6631) and who conducts the mid-60s performances of the Mozart (MS-6344). There is more spice and wit in the remarks, perhaps (as well as handsomer sound, of course), but more lambency in the earlier versions with Busch. In the Brahms, this quality would incline me to favor the reissue over the remark.

The other side of the Mozart disc comprises two more works of Mozart, neither of which involves Serkin: the "Serenata notturna" in D (K. 239) and the much later Adaigo and Fugue in C minor for stings (K. 546). Both performances are fine souvenirs of Busch's warm-heated musicianship at its most characteristic. Some of the Busch Quartet recording from the same period are being made available again from various sources. I would vary much like to see Columbia reissue some of the ensemble's American recordings-most especially the incomparable one of Beethoven's F-major Quartet, Op. 59, No. 1, and the Marvelous Schumann Quintet with Serkin, both of which were transferred to LP back in 1949.

In addition to the two reissues on Turnabout, the Marlboro Recording Society has issued a new recording in which Busch is represented as composer instead of performer, it is his Violin Sonata No. 2 in A minor (Op. 56), played by Serkin and Pina Carmirelli (MRS-9). The Sonata is an ambiable, expansive work, more reflective than brilliant (with a quiet ending), in a "neo-Brahms" vein favored by few composers in 1945, when it was written. It is authoritatively presented, and does not wear out its welcome after two or three hearings - or five or six, for that matter, which is as far as I've gone with it so far.

The recorded sound is first-rate, but 29 minutes for both sides combined seems a bit shortweight for a disc priced at $7.50 and not discounted anywhere.Moreover, my review copy is marred by the sort of warpage that is certain to cause tracking problems or most tone arms.

Short sides are by no means the rule on the Marlboro label. Serkin's 35-minute performance of Reger's Clarinet Sonata (Op. 107), with David Singer, is complete on a single side of MRS-12, and this disc is especially interesting for the companion piece, the premiere recording (the premiere performance, in fact, from a concert of last July 3) of Bach's 14 Canons on the first eight bass notes of the aria ground from his Goldberg Variations.

The Bach material was rediscovered and published only a year ago; the performance here recorded represents the first attempt at a realization for instrumental ensemble. Serkin plays the aria, solo, at the beginning and end of the sequence, and the 14 canons are performed by a group comprising flute, oboe, English horn, two bassoons and 16 strings.

There are several interesting things in the MRS series, which Columbia evidently passed by in choosing Marlboro material for release on its own label. The discs are available for $7.50 each, including shipping, from Marlboro Recording Society, 5114 Wissioming Road, Washington, D.C. 20016. A detailed list of the 12 released so far may be obtained by writing to that address or telephoning 229-3213.