The Philadelphia area is blessed by the professional and amateur musicians of the Jump City Jazz Orchestra. They rehearse weekly and perform twice a month. That’s not merely a statement; it’s also a caveat. Their second CD, recorded live, reflects some raggedness that results from mixing amateurs and pros. But to their credit, it also reflects dedication and commitment behind a 20-piece band willing to tackle complicated charts. Seven of the 18 tracks here come from the Maynard Ferguson book, and what could be more challenging than charts by the likes of Willie Maiden, Bill Holman, Slide Hampton or Don Sebesky? To guarantee a tribute to Ferguson would be memorable, trumpeter Matt Gallagher, whose durable lung power has electrified many Broadway pit bands, was added as special guest. His best efforts: “Bittersweet,” “Birdland,” “Danny Boy” and “Frame for the Blues.” Kudos to all first chairs: their strong phrasing kept the rest of their sections tight. It certainly paid off for the sax solos in Phil Woods’ “Randi.” Nothing could help poor pianist Pasquale Montenegro; his instrument hasn’t been tuned since MF got his union card.