Modern wars need a modern military, light and fast on its feet, and the U.S. Army has changed accordingly. So has its music.

The Army this summer issued an updated field manual for its lyrical forces — more than 100 bands — that formalizes a major change in the way they operate. It makes them more nimble and flexible, just as the Army has done for its fighting units.

Bands have been broken down into components, like rock, blues and salsa groups; jazz bands; brass quintets; and woodwind ensembles, any of which can be sent quickly, alone or together, to remote and dangerous places. A heavy-metal quartet called the Four Horsemen of the Arockalypse, courtesy of the 3rd Infantry Division Band, even has a homemade music video.

The new musical mission matches current military doctrine: the creation of smaller, self-contained forces, like brigades of 3,000 to 5,000 soldiers, that can be put in place more quickly and rotated more easily than an entire division, which is more than three times as large.

The Army talks about music in the lingo it wields for battle. A rehearsal is a "training session." A small ensemble is a "music performance team," aka MPT Wind, and string sections are "elements." Extra reeds and mouthpieces are "redundant supplies." Bands must be able to support "multiple objectives with targeted musical styles."

In the same spirit, the manual lays out the bands’ missions, which are not to be confused with those of musical ensembles that seek to entertain or enlighten. Army bands are not there to cultivate personal creativity, artistic expression or a love for the Baroque. Their job is to sustain warrior morale, inspire leaders, build good will with the local populace, serve at ceremonies and foster military pride. They also play a crucial role at military funerals.

"Bands carry the message of historical relevance, national unity and prevailing perseverance," says the document, "U.S. Army Bands," which was issued in July by the Department of the Army.

The band manual, the first update since 1999, codifies changes that have been happening in the field for several years. It formally remakes the Army’s conception of the band that had been in effect since World War I. It also reflects the way the wars in Iraq and Afghanistan have shaped how the military delivers culture.

"There is not what you would call a big rear area, where Bob Hope would go in and where you would get civilian entertainers," said Col. Thomas H. Palmatier, who helped prepare the new manual. Palmatier is the commander and conductor of the U.S. Army Field Band, one of the service’s elite ensembles, based at Fort Meade, Md.

The surge strategy in Iraq of sending troops to distant outposts "left a lot of soldiers out there where there wasn’t entertainment or morale-type things," he said. The increased use of helicopter transportation in such a conflict zone also argues in favor of smaller groups. The Army band world has adopted an informal motto, Palmatier said: "If it can’t fit into two Blackhawks, it’s not going to happen." (Blackhawk helicopters can generally hold four crew members and 14 troops.)

The high-profile, large-scale Army bands, of course, remain. Along with the Army Field Band, which tours heavily, they include the U.S. Army Band, informally known as "Pershing’s Own" or not so informally as TUSAB. There are also the U.S. Military Academy Band and the Old Guard Fife and Drum Corps. The Army has 30 more bands on active duty, as well as 70 Reserve and National Guard bands. All told, it has slots for 4,600 band members.

Army bands have plenty of company in the other services. The Navy has 13 bands; the Air Force maintains 12 active-duty bands, joined by 11 in the Air National Guard; the Marine Corps sponsors the U.S. Marine Band ("the President’s Own") of White House renown, and a baker’s dozen other active-duty bands.

The military band world, in a sense, represents a vast hidden level of government support for the arts. Would-be Army band members must pass an audition, enlist, undergo basic training and attend the U.S. Army School of Music in Norfolk, Va. The elite bands announce auditions only when openings occur. Otherwise, recruits can voice preferences for division or separate bands where they might be needed.

Almost universally, band members are inducted with the expectation that they could find themselves in a war zone. "We want to make sure they know what they are coming for," Palmatier said.

At the moment, the 1st Infantry Division Band, based in Fort Riley, Kan.; the 3rd Infantry Division Band, based in Fort Stewart, Ga.; and the 1st Armored Division Band, based in Wiesbaden, Germany, are deployed in Iraq. The 101st Airborne Division Band is stationed in Afghanistan. A music performance unit from Palmatier’s Field Band — the Volunteers, a rock group — is on its way to Iraq for a one-month tour. Some 1,300 band members have passed through Iraq and Afghanistan, Palmatier said.

On musician bulletin boards, discussions about Army bands often revolve around prosaic matters like how much student debt the Army covers or how much guard duty and other regular military activities are required. The manual lays out in detail the makeup of each music performance team, labeled B through F, with military precision. The "ceremonial music ensemble," MPT B, for example, is supposed to have percussion, tuba, trombones, euphonium, French horns, trumpets, saxophones, clarinets and flutes. The "small popular music ensemble," — that’s MPT D — has percussion, bass, piano, guitar, trumpet and saxophone, and possibly vocal and amplification elements. There are also brass and woodwind quintet MPTs

The manual divides Army bands into categories: large, usually assigned to an Army command; medium, for the corps level; and small, for division headquarters or individual installations. The bigger the band, the more performance teams.

The document also puts in black and white the obvious changes in musical tastes. "Traditional brass and woodwind groups," while still "vital to overall support," have taken a back seat to pop of all hues: rock, blues, country and "succeeding genres of music." More vocalists have been added to bands.

"That 20-year-old really doesn’t want to listen to symphonic-type music," Palmatier said.

On the other hand, he noted, an old-fashioned brass quintet still has its advantages. It can jump off a helicopter and set up in a field mess hall without the encumbrances of amplifiers, microphones and speakers.

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