Book excerpt: Composer and musicologist Touma provides an overview of Arabic music through history to contemporary production, and elucidates typical musical structures for secular and sacred, instrumental and vocal, improvised and composed music. He also explains the unique modal system and improvisation style. Includes a glossary, a guide to pronouncing the transliterated alphabet, and a discography. A seven-song, 75-minute companion CD is available for $15.98. First published in German in 1989 and previously translated into French and Italian. Annotation copyright by Book News, Inc., Portland, OR