This was a rich year for recordings of previously unexplored classical music as well as outstanding performances of familiar works.

The new In Sync releases showed how good a cassette can sound, and RCA's new Victrola cassette reissues show how economical they can be. We finally got around to D'Indy's inexplicably neglected Second Symphony, though the performance is not of top quality, and also to Shostakovich's much-discussed but long unheard "Tahiti Trot," part of a superb collection of obscure Shostakovichiana on Vox Cum Laude.

To list the dozen most treasurable releases of the year, we must begin with recordings of two Czech operas: the premiere recording of Jaromir Weinberger's "Schwanda the Bagpiper," represented in the concert hall by the famous Polka and Fugue, and "The Cunning Little Vixen," the latest in the series of Janacek operas conducted by Sir Charles Mackerras. Lucia Popp helps to make both quite irresistible, and both sets are well documented. ("Schwanda" is sung in Max Brod's German version.)

There are Czech operas by Smetans, too -- "The Bartered Bride" and "The Kiss," both recorded in Czechoslovakia -- as well as Abbado's hard-hitting "Aida" from La Scala and Carlos Kleiber's "Tristan," but my operatic choices for this short list would have to be Rossini's "Mose in Egitto" under Claudio Scimone (the original Naples version at last) and the new Hungaroton set of "Hary Janos," a most appropriate way to mark the Kodaly centenary. The fine performance under Janos Ferencsik is accompanied by an essay on the patriotic connotions of this beloved comic work.

In the orchestral realm, Carlos Paita's new Bruckner Eighth, even after the strunning series under Guenter Wand and the completion of Karajan's cycle, is one of the finest Bruckner recordings ever. Paita's Brahms' First and Dvorak's Seventh also are tops.

Leonard Slatkin has completed his survey of Rachmaninoff's orchestral works for Vox with a marvelous four-disc set in which four well-known works are packaged with seven unfamiliar ones, including the heretofore-unrecorded first movement of an abortive symphony begun by Rachmaninoff in his teens. Three are chorales; all 11 are done to a turn by the Saint Louis Symphony.

Vaclav Neumann's performance of Mahler's "Resurrection" Symphony is exceptional for the felling of ka2joy it radiates -- totally free of the ceremonialism with which this ecstatic work is so often invested. Alfred Brendel brings a similarly fresh and convincing approach to Mozart's Piano Piano Concertos in B-flat (K. 450) and in C (K. 467), surely one of the high points of his distinguished series with Naville Marriner.

Among the numerous notable solo piano releases, the late Glenn Gould's valedictory recording of Bach's Goldberg Variations is not only outstanding in its own right, but especially poignant in that it brought to an end the an extraordinary musical career that began 27 years earlier with a quite different recording of the same work.

All my clamber music choices involve string quartets: the splendid new set of all the Mendelssohn quartets, played by the Melos Quartet of Stuttgart, which should be a revelation to those who've always underrated this composer's achievements in this realm; the magnificent performances of Mozart's "Hunt" Quartet (B-flat, K. 458) and K. 575 in D by the Panocha Quartet of Prague; and finally the long-overdue first installment of reissues of recordings by the Hollywood String Quartet, possibly the finest ever assembled in this country. THE TOP DOZEN OF 1982

WEINBERGER -- "Schwanda the Bagpiper." Hermann Pray, Lucia Popp, et al.; Munich Radio Chorus and Orchestra, Heinz Wallberger (CBS).

JINACEK -- "The Cunning Little Vixen." Lucia Popp, Dalibor Jedlicka, et al; Vienna Philharmonic, Sir Charles Mackerras (London).

BRUCKNER -- Symphony No. 8 in C minor. Philharmonic Symphony Orchestra, Carlos Paita (Lodia).

MENDELSSOHN -- Complete String Quartets. Melos Quartets. Stuttgart (Deutsche Grammophon).

MAHLER -- Symphony No. 2 in C minor ("Resurrection"). Czech Philharmonic, Vaclav Neumann (Pro Arte).

RACHMANINOFF -- "The Bells"; "Caprice Bohemien"; "The Isle of the Dead"; "Prince Rostislav"; "The Rock"; Three Russian Songs; Scherzo in F; "Spring"; Symphonic Dances; Vocalise; "Youth Symphony." St. Louis Symphony Orchestra, Leonard Slatkin (Vox Cum Laude).

ROSSINI -- "Mose in Egitto." Philharmonia Orchestra, Claudio Scimone (Phillips).

BACH -- Goldberg Variations. Glenn Gould (CBS).

MOZART -- Piano Concertos No. 15 in B-flat (K. 450) and No. 21 in C, K, 467. Alfred Brendel, piano; Academy of St. Martin-in-the-Fields, Neville Marriner (Philips).

String Quartets No. 17 in B-flat, (K. 458) and No. 21 in D, (K. 575). Panocha Quartet (Denon).

HOLLYWOOD STRING QUARTET -- Brahms: Piano Quintet (Victor Aller, piano); Schubert: String Quintet in C major (Kurt Reber, cello); Dvorak: Quartet in F, Op. 96; Smetana; Quartet in E minor ("From My Life"). (EMI import, monaural).

KODALY -- "Hary Janos." Sandor Solyom Nagy, Klara Takacs, et al.; Hungarian State Opera Chorus and Orchestra, Janos Ferencsik (Hungaroton).