Honk! band Environmental Encroachment

Honk! band Environmental Encroachment performs. (Photo: Leonardo March)

The 10th annual Honk! Festival of Activist Street Bands comes Oct. 9-11, but entered this weekend with a nail-biting countdown as well as a list of firsts for the constantly expanding event.

The free festival has a $17,000 crowdsourcing campaign in place to ensure that all of the 28 expected bands can make it to Somerville for the festivities, and as of Saturday morning was still about $3,000 short. Because the campaign is on Kickstarter, this money comes through only if all the funding is pledged by Wednesday morning.

Update on Sept. 22, 2015: With 24 hours to go, the fundraising campaign had exceeded the needed amount by more than $1,000. By Tuesday morning, 260 backers had contributed $18,308.

“It wouldn’t be Honk! without some last-minute surprises,” said Mary Curtin, who has worked with the street music festival since its beginnings in 2006, when a dozen bands launched the tradition in Somerville’s Davis Square, responding to a call by the city’s Second Line Social Aid and Pleasure Society Brass Band.

The phenomena is “rippling across the planet,” Curtain said, with yearly Honk! festivals spreading to Providence, R.I.; New York City; Seattle; Austin, Texas; and Detroit; and Australia and Brazil.

Some of the features of a fully funded Honk!, as laid out in a Wednesday email:

bullet-gray-small The 28 sociopolitical activist street bands that are expected to play this year come from as far away as Paris; Los Alamos, N.M.; New Orleans; and Montreal and Quebec City. (A complete list of bands is here.)

bullet-gray-small Among the Boston-area bands is a new local School of Honk!, based in Somerville, that will organize “walk-ins” for local musicians who are not affiliated with an existing band.

bullet-gray-small Extra activities in the planning stages include a “Visaural: Sight, Sound and Action” art exhibit with a “Honk! Around The World” component at the Nave Gallery Annex in Davis Square; an opening reception Oct. 9; and a possible pre-Honk! gathering in Somerville’s Union Square on Oct. 8.

Traditional festival events start Friday with a Day of Action in Boston during the afternoon; early evening Lantern Parades throughout Davis Square; and evening band showcase at Johnny D’s, 17 Holland St., Davis Square.

Saturday is considered the main event, with continuous band performances from noon to 9 p.m., rain or shine, throughout Davis Square.

Sunday brings a sprawling noon parade from Davis Square to Harvard Square, where Honk! bands participate in Oktoberfest, performing throughout the square in the afternoon and ending with a steady stream of Honk! bands showcased up on the Main Stage.