No two musical instruments look exactly alike, and the subtle differences can be strikingly beautiful. Yet the craft of instrument making has always been relegated to a subordinate position, in the public eye, to the craft of music making.

Now a museum of design, the Smithsonian's Renwick, has given the instrument craftsman proper due with a splendid show called "The Harmonious Craft: American Musical Instruments."

There are 105 instruments in the show, made by 88 persons. "We tried to put together a show that demon strates to state of handcrafted instruments as it exists today, both as to quality and variety," says James Museum of History and Technology. Weaver, an associate curator at the [WORD ILLEGIBLE] The oldest object in the show dates from 1963.

Belonging to Israel Chorberg, American Ballet Theater's concertmaster, with an elegant inlaid medallion above the bridge.

For quality, there is the 1976 violin instruments as a cow's jawbone wired up to make sound, called a "progarmmable portable electronic ten sequence generator cow jawbone with functioning electronics." Or a harp that is a rectangular frame with metal wrenches strung up in it and pitched to the sequence of the scale. It is struck with wooden mallets and makes surprisingly beautiful sounds.

"The only ground rule for this show was that the object be handcrafted," said Weaver, who organized the show with the Renwick's director, Lloyd Herman. "The wrench harp is a perfectly legitimate percussion instrument, though I'll grant you about a 60 percent bet that the jawbone is a puton."

As a result of these limits, harpsichords are in, but pianos are out, because they are in part made mechanically. Likewise, recorders are in but flutes are out.

When the Renwick advertised for submissions last year, they received entries from about 300 instrument makers. The first step in the selection process was for entrants to sends lides or photos of three examples of their work. The entries say much about the character of present-day musical craftsmanship.

"We were deluged with guitars, which seem to be today's most popular instrument," said Weaver.

There are nine in the show, ranging from a French-style baroque instrument with an exquisite ivory rosette in the center; to a sleek, small electric guitar of maple, rosewood, brass and ivory. Both were made in 1977.

"Also, we see solid evidence of the boom in baroque instruments. There were recorders and harpsicords galore. It's amazing, because 30 years ago a good harpsicord was hard to find. But in 1949 two men in Boston, Frank Hubbard and William Dowd, set up a harpsicord shop in Boston and started training craftsmen, who then set up other shops all around the country. By now there must be 30 or 40 shops.

"Conventional string instruments are in shorter supply, on the other hand. That's because they require greater skill and refinement and also because musicians prefer the older ones. The varnish of the 17th-century Italian instruments simply cannot be duplicated today.

"Aside from violins, organs are the only other major instruments in which older ones are more valued."

Among the other highlights of the show:

A small wooden, gothic harp copied from a painting by Hans Memling.

A copy of the glass harmonica invented by Benjamin Franklin, for which Mozart wrote a composite.

A "one-time-only" set of clay and glass objects, beautifully designed, that are meant to be thrown off cliffs and which whistle before they crash at the bottom.

A wooden slit drum made of padauk, maple and walnut.

A 10-course lute with a beautiful, inlaid stripped bottom.

A so-called "cello" that is a sheet of metal bent by a steel string that connects 2 corners. By bending the metal, the composer can change the pitch while drawing a bow across the string.

The show runs through Aug. 5 and is free. Twenty-five of the instruments have been recorded, and can be heard on earphones at the Renwick. The music will be released on a record in December.