CONCERTS in the Houses are generally notable for their charm and enthusiasm rather than their professional polish. Every once in a while, however, the tables are turned and a House offers musical fare in competition with and equally prestigious as that ordinarily scheduled for Sanders Theatre or Kresge Auditorium.

Friday night Kirkland House presented free and open to the public--due to the munificence of Master Arthur Smithies--what was probably the most incandescent pair of performers of the entire Cambridge musical season: James Oliver Buswell IV, a sophomore concentrating in Fine Arts who is nonetheless an established professional violinist, and Fernando Valenti, one of the world's most revered, if himself somewhat irreverent, harpsichordists.

For Buswell it was the third major concert appearance in Cambridge this semester. This time the program consisted of the three even-numbered sonatas for violin and harpsichord by J. S. Bach, for which occasion Valenti's custom-made two-manual, seven-stop Challis (featuring among other things, a 16-foot stop and a metal sounding board) was carted up by station wagon from New York. The combined reputations of composer and performers insured a capacity audience, which as it turned out subsumed the entire range of musical appreciation from hedonism to intellectuality. Some came to analyze, some to envy, but most to enjoy.

The latter was almost impossible not to do. Generally speaking, Buswell and Valenti played their short, concentrated program with the aplomb and assurance of which only professionals are capable.

Although Buswell's usual obtrusive stage mannerisms were curiously more restrained than usual, he still indulged in a great deal of theatrical breathing and a series of almost grotesque attempts at beatific smiles at moments whose exquisiteness he seemed particularly desirous of pointing out to the audience. The trouble with these antics is threefold: they are aurally and visually distracting, especially in a room the size of the Kirkland JCR; they are didactic and insulting to an audience generally capable of appreciating Bach's subtleties on its own; and, most important, they are bound to distract a performing musician from his real business, which is to channel his expressiveness into the sounds he is producing. If instead it is trapped by some sort of external physicality, it is ultimately the music that suffers. This was the case with Buswell's slow movements, which for all his contortions seemed to communicate respect for the music rather than genuine feeling. Due possibly to a certain degree of nervousness, Buswell also had a surprising number of lapses of bow control, with a tendency toward a glassy tone whenever he wanted to play softly. On the surer grounds of the more aggressive rapid movements, his playing was marred only by his arbitrary choices of moment for echo effects, a habit detrimental to the continuity of Bach's long, carefully contoured phrases.

VALENTI by contrast was poker-faced throughout the performance. Like Buswell he exhibited a modicum of uneasiness in the first sonata but went on to demonstrate the tremendous tensile strength of his fingers and, at the same, time, his amazing agility. His playing was motoric but not without subtleties of phrasing and dynamics. Together with Buswell, he was at his best when the music was at its most kinetic. At times his registration was somewhat arbitrary and misconceived, such as in the third movement of the Sonata in A, where he played the basso continuo left hand on the more loudly voiced manual, and the more important right hand line (in canon with the violin) on the softer one. His frequent use of the lute and leather stops became annoying, largely because of the basic ugliness of these stops on this particular harpsichord, as well as the instrument's generally unpleasant metallic tone.

Another unfortunate disadvantage of the harpsichord is its tempermental proclivity for going out of tune. True to form, the Challis reacted to Friday's overheated JCR and went disappointly flat, a fact which was only exacerbated by Buswell's tuning and consistently playing sharp.

All these, however, are petty considerations compared to the sheer feat of performing that much Bach--any musician's ordeal by combat--on one program. Almost consistently competent on a professional level, the combined efforts of Buswell and Valenti frequently achieved real excitement as well. Hedonist or intellectual, that is as much as anyone can ask.