About the bandoneón "It's the difference between a lemon and an orange," Piazzolla once said in an interview in New York. "The bandoneón is an orange, the accordion is a lemon. The accordion has an acid sound, a sharp sound. It's a very happy instrument. The bandoneón has a velvet sound, a religious sound. It was made to play sad music."   Thanks largely to Piazzolla’s repertoire the bandoneón has suddenly and surprisingly, made its way into the concert hall. "The instrument today has been universalized," says David Binelli, Argentine bandoneón player. "In the right hand, you get a timbre that is very clear, like an oboe or violin," he says. "The left hand gives a low sound like a cello or saxophone." He points out that the instrument can sound as many as eight different pitches at one time.   Technically, the bandoneón is a member of the portable reed organ family.  Like its cousin the accordion, the performer plays while operating the expanding bellows in the center of the instrument. The accordion, however, has a piano‑style keyboard, while the bandoneón is operated by button-like keys. Unlike the accordion, with its keyboard to the right and buttons (producing bass notes and chords) to the left, the bandoneón has 33 buttons on the left and 38 on the right, each producing one of two tones, depending on whether the bellows are being compressed or expanded.  Technically a large concertina with chromatic capabilities, the bandoneón can play all 12 notes of the scale.   Invented by Heinrich Band in 1854 for religious music in organ-less churches, the bandoneón made its way from Germany to the brothels of Buenos Aires. By the early 1900’s, small tango groups of violin, piano, and bandoneón started cropping up.  This set the mold for the orquesta tipica criolla of bandoneón, strings, and piano.  In a sense, Astor Piazzolla’s orchestral writing is an expansion of this idea.  His Concierto para bandoneón is scored for bandoneón, strings, and percussion. The bandoneon’s association with cabaret‑style music led to its inclusion in two operas of Kurt Weill. Ironically, its association with the tango has led to its current entry into the concert hall.