When someone mentions chamber music, the first example to come to mind is often a string quartet. Furthermore, one might reasonably expect that a concert featuring a string quartet would consist primarily of string quartet music.

But Chamber Music Hawaii had a surprise in store for its season opener.

The Galliard String Quartet and Friends assembled an entire evening of engaging pieces without including a single straightforward string quartet.

No two pieces shared the same instrumentation: there was a trio for flute, oboe and viola and another one for flute, violin and viola; there were quartets for oboe and different combinations of strings; and there was even a quintet for flute and — aha! — string quartet.

In every piece, members of the Galliard String Quartet, violinists Claire Sakai Hazzard and Hung Wu, violist Mark Butin and cellist Karen Bechtel, were joined by one or both of their fellow Honolulu Symphony "Friends," oboist J. Scott Janusch and flutist Claire Starz Butin.

When Chamber Music Hawaii combines musicians from its three ensembles (the Galliard String Quartet, Spring Wind Quintet, and Honolulu Brass), it calls the mix a "tresemble." This concert combined only strings and winds, presumably making it a "duesemble."

Most of the program came from the 20th century's wealth of chamber works. The only classical piece was the second of Beethoven's two Serenades, Op. 25 from about 1800, one of his many early works usually passed over in favor of his revolutionary middle and late works.

Serenades were not really concert fare, although they are generally heard that way now. Rather, they were more casual music, as indicated by their simple forms and numerous repeats — a perfect opportunity to practice recognizing musical form.

The other four works, all from the 1920s to 1940s, were unified mainly by their variety.

Gustav Holst's "Terzetto" had the instruments playing in three different keys, and often in different meters, as well, which does not sound as odd as you might think, but instead comes across as both clever and charming.

Both Benjamin Britten's "Phantasy" Quartet, an early (Op. 2) work that presaged his genius for capturing imaginative worlds in sound, and Bohuslav Martinu's entrancing "Mazurka-Nocturne" featured Janusch's beautifully arched oboe solos.

In a program as diverse as this, everyone finds a favorite piece.

For me, it was Alberto Ginastera's three-movement "Impressions of Puna." The first movement highlighted a cadenza-like midsection by Starz-Butin imitating a Quechua Indian flute called a quena, used throughout the Andes. The second movement's swaying "Cancion (Song)" led into the folk-inspired "Danza," with its delightful interplay between Starz-Butin (flute) and Hazzard (violin).

Each of Chamber Music Hawaii's concerts this fall presents mixed ensembles, whether duesembles, tresembles or augmented ensembles.

The Spring Wind Quintet will perform as "Spring Winds & Friends" in October; the Tresemble will morph into a "Trio of Trios" in November; and the Honolulu Brass Choir will perform with organ and percussion at St. Andrew's Cathedral in December.

For program and ticket information, visit www.chambermusichawaii.com, and enjoy the season.