IT HAS BEEN FASHIONABLE for a long time to put Tchaikovsky down. His genius as an orchestrator is overlooked, his gift for melody is actually held against him, and in general he has just never been forgiven for writing music so extremely easy to like. His Fifth Symphony, which persists in being monstrously popular, even beloved, has been a favorite whipping boy in this silly business.

Tchaikovsky conducted the first performances of the Fifth nearly 90 years ago, and in the five years he lived after that he never quite made up his mind about whether he liked the work. Had he not been so indecisive, he might have observed, as Shostakovich did of his Ninth, that "orchestras will love to play it, and the critics will love to damn it." Of course, the Fifth has had its scholarly defenders, among them the illustrious Donald Francis Tovey, who summed up his long analysis of the work by noting that Tchaikovsky "is thoroughly enjoying himself. And I don't see why we shouldn't enjoy him too."

Most of us have done just that - musicians as well as audiences. Arturo Toscanini was one of the few major conductors who never recorded the Fifth; Wilhelm Furtwaengler and Bruno Walter didn't, either, but both of them did perform the work with some frequency. Eugene Ormandy and Herbert von Karajan have each recorded it four times - and have been among its most consistently satisfying interpreters. Seiji Ozawa's second recording of it, recently released by Deutsche Grammophon (2530 888), brings the number of Tchaikovsky Fifths listed in the current Schwann catalog to a grand total of 27, and two or three more may well materialize by the time these words appear in print. It may be impossible to pin down a single "best" among these, but there are some exceptionally good ones.

For the most part, the best ones do not turn up among the "integral" packages of the Tchaikovsky symphonies, of which there are no fewer than seven in circulation at present. The Fifth is the least attractive component of Mstislav Rostropovich's Tchaikovsky box with the London Philharmonic (Angel SGE-3847), mainly because of the very slow tempos in three of the four movements. The Fifth still surviving from Igor Markevitch's cycle with the London Symphony Orchestra, however (Philips 802 703LY), is one of the finest ever.

Not everyone will respond to Markevitch's aristocratic approach. The first movement's third subject, for example, an invitation to wallow that few are able to resist, is dealt with quite briskly by him, but the subtle build-up to the real climaxes gives them unique power and conviction. Markevitch puts - or perhaps simply finds - true nobility in the work as he does in all of Tchaikovsky's music. Interested collectors should grab this while they can (and continue hunting for Markevitch's all-surpassing Little Russian, on the unaccountably deleted Philips 835 390LY).

Otto Klemperer's was another strikingly noble account of the Fifth, available until recently both on Angel S-36141 and in a three-disc set with Symphonies Nos. 4 and 6 (SCB-3711). The orchestra was the "old" Philharmonia at its peak. Perhaps these distinctive performances will find their way back on Seraphim.

George Szell's interesting (and exciting) performance is still available on Odyssey Y-30670, but sonic considerations keep it from being a top contender. A sonic fluke, too, disqualifies the surprisingly attractive version by the late Josef Krips and the Vienna Philharmonic on London STS-15017. The performance itself is one of the best, and the sound has a richness that belies its age, but in the middle of the final movement the continuity and the total image are shattered by a sudden change in the level: one would not think London would let such a thing pass.

The new Ozawa Fifth, with the Boston Symphony Orchestra is a much stronger one than his earlier Chicago Symphony version (RCA LSC-3071). The BSO is in top form, the recording is wide open, and the fairly straight-forward performance yields a good deal of satisfaction without any surprises. The same may be said of about a dozen other versions, except that the others are less splendidly recorded.

Pierre Monteux's recording with the same orchestra, recently remastered for RCA's Gold Seal series (AGLI-1264) is still a glorious realization of the work, one in which Monteux's unself-conscious elegance makes everything seem just right. The sonic differences between this and the new Ozawa are offset by the Maitre's greater subtlety and all-round character. (A later Monteux recording, with the NDR Orchestra of Hamburg, should be out on Turnabout soon.)

Almost as opulently recorded as the new Ozawa, and with more of the emotional stops out, are two other recent releases: Karajan's latest version with his Berlin Philharmonic (DG 2530 699) and Bernard Haitink's warm-hearted account with the Concertgebouw Orchestra (Philips 6500 922), both of which are also available in good cassette editions. These discs and the Markevitch each list at $8.98 now, and are worth every penny; the refurbished Monteux, at $4.98, is a marvelous buy and may well serve as a sort of norm for performances of the work.