Plunk!

The voice of the plectrum is heard in our land.

Twang!

A string is plucked, tension is released, and the air vibrates.

This week, with two concurrent plucked-string festivals -- one for guitar and another for the harpsichord -- Washington will be plunking and twanging in all directions.

The sounds are not exactly unheard in Washington the rest of the year; there are some splendid, often-used harpsichords at the Smithsonian, and the guitar shop founded here by the late Sophocles Papas is internationally known. But from the beginning of the First International Classical Guitar Congress, Tuesday at the University of Maryland, to the end of the Southeastern Historical Keyboard Society's Sixth Annual Conclave, next Sunday at the Smithsonian, the city will be vibrating more than ever on the special wavelength of the plucked string.

At first glance, there seems to be little similarity between the two instruments. The guitar is portable and held in the player's lap. The harpsichord looks like an undernourished piano trying hard to grow up -- though its fans claim it is no such thing.

But if you try to look back into the depths of prehistory, you find it it quite possible that both instruments are remote descendants of the bow and arrow.

The plunk of a vibrating string has had special overtones of happiness and fear since primitive times -- since the days when a twanging bowstring next to one's ear might mean fresh meat on the table or an enemy eliminated.

Today, when we get our meat at the supermarket and take our enemies into court, the sound of vibrating strings is no longer a matter of life and death. But it is still music to our ears, as it was to Homer at the dawn of western culture.

At the climax of the "Odyssey," when the hero is preparing to take revenge on his enemies, the poet describes the action in musical terms. Ulysses strings his bow "like a man skilled on the lyre, stretching a gut string to a new peg." Homer's word for "string," "chorde," still lives in English. And it still has a musical meaning ("chord") as well as a functional meaning ("cord"). When Ulysses plucked the string to test its tightness, Homer says, "it answered with a beautiful sound, like the note of a swallow."

The plucked string is probably not the earliest medium of human music-making. We may assume that the voice and percussion (perhaps clubs beating on shields for a war dance) found their artistic forms sooner. But these are not civilized noises. The sound of a plucked string denotes a higher level of culture. The arrow (one of humanity's first mass-produced, standardized, disposable artifacts) implies a social structure that is not necessary for a shouting match or a clubbing.

At our current stage of evolution, the music of plucked strings, elaborated far beyond its primitive roots, is still one of humanity's more civilized activities. And at its best, it retains the primeval power to stir and soothe the savage in us. The greatest music always includes some elements of irrationality, something that speaks to deep, ancient layers of the soul.

Modern equivalents of Homer's "man skilled on the lyre" will be swarming to Washington this week, spearheaded by harpsichordists Kenneth Gilbert, Anthony Newman and George Lucktenberg, and guitarists Eliot Fisk, Laurindo Almeida and Manuel Barrueco, to name only a few. A highlight of the week will be a memorial concert in honor of Sophocles Papas, who made Washington a major guitar center, Friday in Gaston Hall, Georgetown.

Newman will attend the harpsichord festival as a performer and the guitar festival as a composer. Otherwise, most people at these two gatherings will probably be too busy to talk much to one another.

But they have a lot in common. The classical guitar today is, in many ways, closer to the harpsichord than to the modern, electrified rock guitar. The guitar and the harp both seem to be descendants of musical bows that are still played in some primitive cultures and are considered the forebears of the chordophone ("sounding string") family.

It might be hard to shoot an arrow with a modern guitar, but you could try with a harp, which is something like a large bow equipped with numerous differently tuned strings. And what is a harpsichord but a harp laid on its side with a keyboard attached? The guitar, which changes pitch by "stopping" the strings at various points along its neck, is a later evolutionary development than the harp -- which, in its primitive forms, can derive only one pitch from each string.

But the use of the keyboard makes the harpsichord a more "advanced" instrument than the guitar in several respects. The harpsichordist never touches the strings; he touches a key, which raises a jack, bearing a plectrum (usually made of leather or goose quill), which plucks the string, producing the sound. This is a complex operation, but the complexity takes place in the mechanism, allowing the performer to concentrate on technique, phrasing and musical structures.

The guitar (whose historic lineage is much older than the harpsichord's) has no such mechanical aids. The fingers of the player's left hand (usually calloused to a bonelike hardness at the tips) stretch and bend into pretzel shapes to produce the necessary chords, while his right hand (usually without a plectrum) must be trained so that each finger (including the thumb) can operate with a certain autonomy.

Because his instrument is less automated, the guitarist must work a lot harder for simpler results. Music for the harpsichord can be more complex. And considering the relative amount of work required to produce each note, a harpsichordist should be able to play a lot longer than a guitarist before fatigue sets in.

The guitarist has some compensation in his more intimate contact with the instrument. He can produce a wide variety of tonal effects by changing the pressure, the angle of attack, the part of the finger or fingernail used to do the plucking, or the place along its length where the string is plucked.

A harpsichord can approximate some of these effects by using different stops, but it cannot "bend" a note -- alter its pitch in mid-note -- as a guitarist can do by moving his left hand. That ability was built into the clavichord, a predecessor of the harpsichord that may have the most subtle and delicate sound of any keyboard instrument but lacks the power to fill a modern concert hall.

Power is the distinctive quality of the harpsichord's descendant, the pianoforte, whose name in Italian boasts of its ability to play softly ("piano") or loudly ("forte") -- a kind of achievement unavailable to the harpsichord. This power is based on its use of hammers, worked by the keyboard, that transfer the player's varying finger pressures to the tuned strings. It made the piano the king of the recital hall for more than a century before the gentler-voiced, older instruments began their comeback.

The extent of that comeback should be measurable by the number of people who attend this week's two plucked string festivals. And whatever their points of disagreement, the fans of the guitar and of the harpsichord should be able to harmonize in their disapproval of the piano.

Isn't there something too primitive, after all, in a musical instrument that makes noise by hitting strings with a kind of club?