MOST AUDIO EXPERTS agree that the compact disc (CD) is the most important innovation in sound reproduction since the introduction of electrical recording nearly 60 years ago.

Among its unarguable advantages are the absence of disc warpage, scratches, clicks, pops, blisters--surface or background noise of any kind. With an entire hour's program on a single side, there are no inconvenient "turnovers"--no more breaks in the slow movement of the "Eroica" or the "Fantastique." There is no wear, on either the disc itself or the pickup unit, since nothing touches the playing surface but a laser beam.

But what of the musical quality? The compact disc is very impressive, but it does not appear, at its present stage, to represent fully the current state of digital technology or, in fact, to be clearly superior to the finest LP discs. There is a vividness and bloom on the best LP sound that as yet eludes the CD.

Still, the CD's shortcomings may not be apparent at all unless comparisons are made with absolutely top-quality LPs played on absolutely top-quality turntable systems. The "average" or "typical" home music system is not in the running, as the cheapest CD player costs almost $1,000, but the finest combinations of conventional turntable, tone arm and pickup cartridge, costing perhaps half again as much as the CD player, will show clearly the areas in which the CD has yet to catch up.

For my own comparisons I used the new CD editions of 22 recordings I had reviewed earlier in their original release on LP. Those that most seem to deserve comment are discussed below.

The three CDs that sounded closest to their respective LP editions--virtually indistinguishable from them, in fact--were those that came not from original digital masters, but from analog tapes remastered digitally for the new format: Bernard Haitink's superb recording of Debussy's Three Nocturnes and "Jeux" (Philips 400.023-2; LP: 9500.674), Kiril Kondrashin's fine "Scheherazade" (Philips 400.021-2; LP: 9500.681) and Luciano Pavarotti's collection of opera arias (London 400.053-2; LP: OS-26384).

Some of the arias in the Pavarotti collection were recorded as long ago as 1971, and there is a variable level of realism and presence through the sequence, as there is on the LP. The Haitink and Kondrashin recordings, both made in the late '70s, were prominent among Philips' demonstrations of the quality achievable through analog means with careful processing; they are stunning in both formats.

Of the 19 CDs I heard with LP counterparts of true digital origin, two on London struck me as exceptional--not surprisingly, since that label's digital LPs have consistently been among the most impressive from any source. Riccardo Chailly's Rossini overture collection (London 400.049.2; LP: LDR 71034) is a knockout and, I think, the most all-round satisfying of all the CDs I've auditioned, with splendid presence and depth. Vladimir Ashkenazy's Sibelius Fourth (London 400.056-2; LP: LDR 71019), with its sumptuous exploitation of the orchestra's low end, is similarly impressive, with terrific bite in the symphony's opening and a particularly effective "open-air" frame around So derstro m's radiant voice in "Luonnotar."

But Solti's Chicago "Pictures at an Exhibition" (London 400.051-2; LP: LDR 10040) seemed to lack vibrancy in comparison with its LP edition; on CD the great Chicago brass sounds merely powerful, without that dimension of almost frightening realism felt on the LP. This lack of vibrancy is the one complaint I found repeating itself most persistently in nearly all the other comparisons between CD and LP--exceptions being Julian Bream's arrangements of piano music by Albe'niz and Granados (RCA RCD 14378; LP: ARC1-4378), where the guitar is abundantly vivid, if perhaps a little too close up, and a selection of "Messiah" excerpts (RCA RCD-14622; LP: ARC3-4352), in which the voices again have that nice quality of airiness about them and the range of the instrumental writing fits very comfortably within what CD handles with distinction.

That range at present is a bit circumscribed. Despite the CD's striking superiority in terms of dynamic range, channel separation and overall distortion ratio, its frequency range is behind the LP's, and this shows up most conspicuously at the high end, accounting for a certain lackluster character, an absence of shimmer or vibrancy. (Some CD enthusiasts insist it is our accustomed tolerance for distortion that leads us to hear the CD's total freedom from distortion as limitation of the high frequencies, but others do acknowledge it as a problem.)

This is the factor that has turned the Smetana Quartet's eloquent performance of Beethoven's "Rasumovsky No. 1" (Denon 38C37; LP: OF-7168-ND) into a bland, homogenized sound, without impact; it similarly dulls Previn's magical texture in Ravel's "Mother Goose" (Philips 400.016-2; LP: 9500.973). It is what has robbed Eduardo Mata's competent but undistinguished performances of Ravel, Gershwin, Dukas et al. on various RCA compact discs of the little charm and vivacity that had shown up on LP, and it mitigates the impact of Levine's outstandingly fresh "New World" (RCA RCD-14552; LP: ARC1-4552) and Karajan's otherwise staggering and sumptuous readings of Holst's "The Planets" (DG 400.028; LP: 2532.019) and Strauss' "Alpine Symphony" (DG 400.039-2; LP: 2532.015). Karajan's "Eine kleine Nachtmusik" (DG 400.034-2; LP: 2532.031) fares much better, being mostly a "midrange" work, but on his CD of Tchaikovsky's Serenade for Strings and Dvora'k's Serenade for String Orchestra, Op. 22 (DG 400.038-2; LP 2532.012), there is a jarring change in output level from the Tchaikovsky to the Dvorak.

The first LPs, 35 years ago, had nothing like the richness of the finest contemporary 78s, and many of the early stereo discs showed less success than the finest monophonic LPs in dealing with balances; in both cases astounding advances were made in very little time. CD is already much, much closer to matching the finest analog LP, and in several significant respects dramatically surpasses all analog standards.

We might wish the industry had waited a few more months to offer CD to the public. But now that CD is here, and the industry has at least shown enough responsibility to concur on a single "true digital" format, it seems safe to say that within a year or so the few shortcomings noted will have been corrected to realize in full the awesome potential of this exciting new system, and both the players and the discs may be available more economically as well as more abundantly.

My own feeling is that it would be well to wait for this, but those who decide to take the plunge now are likely to find more to fascinate them than to disappoint them.