It doesn't mean, as I first thought, that they've lost their brass section. "Wind symphony" is essentially another term for "concert band," though with a different connotation. The group's president, Jasmine Britt, explains:
Community band originates from the practice of many towns in the beginning of the 20th century having their own local wind band, where anyone could sit in play and the band was at most times in the service of patriotism, playing marches and patriotic tunes.
In the 1950s, Fredrick Fennell contacted 100 composers to specifically write more artistic pieces for Wind Ensemble or Wind Symphony, which were smaller in size than most community bands and served a more musical purpose. We changed our name to Brooklyn Wind Symphony to honor and support those advances in wind-band artistry and to more accurately reflect the pieces that we perform.
While our group does serve the community by enriching the cultural landscape of North Brooklyn, it has also grown to serve the personal musical development of the adult amateur musicians who desire to play more abstract and aesthetically involved pieces. Additionally, many of these musicians come from Long Island and New Jersey for the love of growing musically in addition to performing to increase the cultural landscape of North Brooklyn. Therefore, by broadening to "Brooklyn", we acknowledge the area we serve, but keep it from being limited to one location. And "Wind Symphony" reflects the literature that we typically perform.
The Brooklyn Wind Symphony's fundraiser is Friday October 15 at 7 p.m. at Brooklyn Fire Proof, 119 Ingraham Street. More info here.