Both of the new HGC-RCS records are excellent, although in very different ways. Both are marked by first-rate choral singing and marred by unfortunate technical lapses.

The mass, together with the famous Alleluia, is one of the most important records issued this year. Quite aside from its other merits, it is a considerable tour-de-force, in that it solves a serious problem for American composers: an English text can often make the most exalted choral music sound like Gilbert and Sullivan, or worse. Some of the best of Handel and Purcell sounds more than a little ridiculous because of this.

Randall Thompson avoided the language problem in the Alleluia, as Woodworth observes in his notes, by using only the single word of the title. But he met it squarely in setting his mass to an English text, and he emerges triumphant. Except for an excessive diminuendo on "invisible," every word is perfectly set forth in the music, especially in the Gloria and the Credo, while each of the various parts is uniquely treated, the mass remains a unified and very beautiful whole.

Thompson supervised the recording of the two works, and he has every reason to be pleased with the singing. The Glee Club and the Choral Society have matched the excellent performance they gave at the premiere of the mass last spring.

As for the recording its great merit is that it keeps perfect balance; most choral records sound as if there were twenty sopranos for every bass. However, the transfer from tape to disk was sloppily done. The review copy had serious pre-echo, intemittent hiss, and a series of clicks which sounded like liconic castanets. Furthermore, neither record has any lead-in grooves; so that the first moments of each side are lost unless the needle is put on with a loving and very steady hand.

The Christmas disk has somewhat better surfaces, and the same almost matchless quality of choral singing. The assortment of short pieces has more variety than the mass, and gives the HGC-RCS the chance to display considerable breadth of technique. They approach each carol with appropriate vigor or with calm, so that they are somehow able to sound festive without sounding like the YWCA Christmas party.

The surpassing merit of the record is the balance of the selections between the familiar and the obscure. Adeste Fidelis is included, but so is a very simple and fine carol by one John Billings, called A Virgin Unspotted. The unhackneyed pieces, together with the unhackneyed approach, remove the record from the realm of Christmas tree baubles and Muzak in Filene's basement.

Both records are worth anyone's five dollars, and both are a complete success for the Glee Club and the Choral Society. But the HGC-RCS is not heard to best advantage here, as they have been in their Berlioz recordings for Victor. They would do well to remove themselves from the indelicate clutches of Cambridge Records Inc., posthaste.