The Delaware Symphony is not an ensemble most people would think of as cutting edge, but a new marketing technique is being pioneered in Wilmington which larger orchestras probably should have thought of years ago. “Instead of the traditional orchestra pamphlet simply listing programs and prices, which is often geared toward listeners who already know what they want, the Delaware Symphony’s “Guidebook” takes potential ticket buyers gently by the ear and leads them through the season’s repertoire.” The season brochure is accompanied by a 30-minute CD which features musical samples, and the orchestra’s music director talking about the music.