THE TAPE CASSETTE has taken another giant step toward full acceptance as a high-fidelity medium with the first release in this format of no less than 50 items from the prestigions, low-priced Odyssey catalogue.

Odyssey, a half-price subsidiary of Columbia Records, features in its disc-catalogue some of the greatest musicians of our century - Bruno Walter, Jean-Pierre Rampal, Sir Thomas Beecham and the Bodapest Quartet, among others - as well as the fascinating excursions into 18th-century music done by the late Max Goberman for his Library of Recorded Masterpieces in the 1960s and reissued at a lower cost after his death. The first issue of Odyssey cassettes focuses on items from the sterep era and for the most part on performances that have long been accepted as classic statements of the music.

Lacking the time and space to give due attention to all 50 cassettes, I have chosen to review a few that I have long cherished in heir disc editions. A comparison of the discs with the cassettes shows, in general almost identical sonic qualities - so close, in fact, that the comparison is probably between th components used for playback (in this case, a Nakamichl 500 cassette deck and the new Shure V15 Type IV cartridge, which is particularly good on older records that have become warped and/or exposed to dust). In a few cases, the disc showed a slight advantage over the cassette at the high end - a slightly richer fiute tone, for example - and there are some cassettes from other companies such as Advent that have a more spectacular sonic impact because they are recorded on the wider-range chromium dioxide tape: But the sound of the cassettes listed below is excellent; if it sets no new standards, it easily meets those that prevail in the industry for cassettes costing twice as much.

The performances are equally excellant; in most cases, the music is part of the basic repertoire, available in numerous recordings at a level of quality where personal taste is the final determining factor, but all of the performances below can be recommended, even without considering the price, as interpretations at the highest level.

From Bruno Walter and the Columbia Symphony, an ad hoc recording orchestra that was assembled specially for him in the final years of his life, I have heard and recommend the warmly lyric, beautifully delineated performances of Dvorak's Ninth (New World) Symphony (Odyssey YT 30045) and the same composer's Eighth Symphony (YT 33231), which lacks a nickname but has even more charm than the better-known, later work. In Mahler's First Symphony (YT30047). Walter encounters strong competition from Jascha Horenstein conducting the London Symphony Orchestra (Advent cassette D 1019). Walter's interpretation and sound are beautiful, but Horenstein's recording has more clarity and impact, and his treatment of the work's dramatic conclusion is overwhelming. I would not want to part with either version, but if I had to live with only one, it would be Horenstein.

Jean-Pierre Rampal, particularly when he has Robert Veyron-Lacroix with him at the harpsichord, leaves the listener with no agency of choice at all. A comparison of their performance of the complete Bach flute sonatas (Odyssey YT 34630 and 34631, two cassettes) with the recently issuse Deutsche Grammophon Archiv edition by flutist Aurele Nicolet and Harpsichordist Karl Richter (Archiv $310 368 and 369, two cassettes) shows Rampal in a class by himself, both for pure technique and for comprehension of the music's emotional implications. This is true despite the outstanding quality and scholarly precision of the Archiv production and the fact that, unlike Odyssey, Deutsche Grammophon includes a booklet of program notes with each cassette.

Rampal and Veyron-Lacroix deliver the same high level of musicianship in the complete flute sonatas of Handel (Odyssey YT 32371 and 32372, two cassettes), gracefully melodic music which is still not as well known as it deserves presents most attractively. On Odyssey YT 32890, which presents two flute concertos by Bach and two by Telemann, Rampal's exquisite solo work makes the orchestral contribution (by Karl Ristempart and the Saar Radio' Chamber Orchestra) sound a bit routine, but at its worst this recording is quite adequate and at its best it superb.