Every summer for the past 15 years, a selection of the most skilled violinists, violists, cellists and pianists from around the world converge for the Music@Menlo festival: a three-week celebration of chamber music. And each year, the festival focuses on an overarching concept that ties it all together. Past themes have featured individual composers or geographic areas, such as "Russian Reflections" in 2016. This year, the festival is saluting a specific instrument: "The Glorious Violin."

The festival's brochure describes the violin as "a miracle of technology that has not required an upgrade for over 300 years." Indeed, the violin has had superficial accessory upgrades -- some different types of strings and chin rests -- but Antonio Stradivarius' original dimensions and materials are still emulated to this day (impressive in an era in which technology is obsolete after just a few years).

Music@Menlo's seven main concerts are a journey through the violin's history in the Western world from the 17th to the 20th century. The story begins in Italy, with the baroque music of Corelli and Vivaldi, as well as lesser known-composers such as Locatelli and Uccellini. The narrative then progresses to the German classical style, with Haydn, Mozart and Beethoven. Next comes the romantic era, with master composers such as Mendelssohn, Schumann and Brahms, as well as specialized virtuoso violinist-composers such as Niccolo Paganini, Joseph Joachim, Eugene Ysaye and Fritz Kreisler. The final two concerts explore music from the late-19th and early-20th centuries, with Shostakovich, Martinu and Dohnanyi.

John Corigliano is the only living composer featured in the festival, and his "Red Violin Caprices" seem the perfect choice for a series chronicling the history of the violin (they were composed for a 1998 film that tells the story of a single violin's adventures in the hands of several generations of players.)

One unique highlight of the festival is Sean Lee's July 21 performance of the complete set of Paganini's 24 caprices -- a rare feat for the notoriously difficult compositions. Lee studied with a Paganini specialist and has a YouTube channel with point-of-view videos of him playing Paganini. He loves playing scales and described "tackling the technical challenges" as "lots of fun."

Another noteworthy program is Yura Lee's "Violin Universe" concert (July 26), which will include not only virtuoso masterpieces such as Bach's "Chaconne" and Ysaye's solo sonata but also Norwegian and bluegrass fiddling to be announced from the stage. A fiddle and a violin are basically the same instrument; the difference is in the approach to the music and the overall style of playing. In classical violin music, all the notes and dynamics are carefully notated by the composer while in fiddle music, rooted in folk traditions, the musician is free to embellish and improvise his or her own variations.

This year's "Encounter" lecture titles include: "From the Birth of the Violin to J.S. Bach and the Glory of Cremona" tracing the ancient history of stringed instruments, "The Devil's Violinist: Niccolo Paganini" and "The Violin Today," which will feature a violin maker in a panel discussion with festival artists on topics ranging from pedagogy to instrument construction.

In addition to Music@Menlo's thematic main concerts, the "carte-blanche" series that allows artists to curate their own programs, and lectures that tell the story behind the music, the festival also offers a young-performers program to train the next generation in this special sub-genre of classical music.

"Very, very intense" is how festival co-director Wu Han described the preparation and audition process. "Menlo Institute has become a premier program in the country. These youngsters have to audition rigorously in order to get into Menlo. They have to compete nationally in order to get into the program." The 40 young artists selected will have a daily schedule of rehearsals, coachings, master classes and concerts, plus their daily personal practice.

As opposed to orchestral music, in chamber music, each player has their own unique part, with ensembles varying in size from one to eight players. There is no conductor or drum to keep the beat: The musicians literally have to breathe together and match each other's pitch with accuracy of less than a millimeter on the fingerboard.

"Musicians used to take summers off," said co-director David Finckel, "There didn't use to be so many festivals and activities like there are now. The summer has become very busy and very demanding, repertoire-wise."

Finckel and Han have been described as chamber music's "power couple." Having recently returned from a tour of China and Taiwan, they deal with jet lag by getting up at 4 a.m. to practice. They stressed the need to "religiously" keep their instrumental technique in shape, describing the classical music world as "not very forgiving." Prior to arriving at Menlo this summer, their concert and teaching schedule has also taken them to Kentucky, Minnesota, St. Petersburg, Russia, Aspen, Colorado, with pit stops in New York. But Music@Menlo, they agreed, is as a highlight of their summer.

The festival holds events every day between July 14 and August 5, including free, public performances and those requiring a ticket. Events are held at Menlo School and Menlo-Atherton High School. For complete info, schedules and tickets, go to Music@Menlo.