jbl synthesis scl 6xlJBL Synthesis SCL 6XL In wall speaker for home theater with wide coverage and flexible placement JBL Synthesis SCL 6XL is an in wall speaker developed for home theaters where you want a solution that can cover multiple seats without losing cohesion in the sound. It works as an LCR behind an acoustically transparent screen or as a surround speaker in larger rooms. With a compression driver, HDI horn, and four 6. 5 woofers, you get a speaker that