I have since found out - easily enough from the internet - that the band was formed in 2011 and is based in Milwaukee, Wisconsin. That's more than 1000 miles north of New Orleans; or, to put it another way, it's on the west shore of Lake Michigan, about 90 miles north of Chicago.
The Extra Crispy Brass Band aims to play in the tradition of such New Orleans brass bands as The Dirty Dozen and The Olympia. Indeed, the band was founded and is led by trombonist Gregory Cramer, who used to live in New Orleans.
As is common practice with brass bands, there are no chord players (banjo or guitar) but they double up with two trumpets, two trombones and have at least one saxophone. The percussion (two players) is the essential department. Such bands of course usually have as their basis great rhythms laid down by the drummers and sousaphone, generating pulsating riffy excitement. This band certainly works that way.
For a well-made video to give you some idea of their appearance and sound, CLICK HERE - where they are playing Royal Garden Blues.