This building is placed in one of the most important road axis of Barcelona, where two main streets joins at Les Glories square. There are also three subway and tram lines just in front of the Auditorium. These circumstances required the design of important vibrational treatments and reinforced sound insulation solutions. The building is totally floating and even the Auditorium ends with a totally glass rear wall, a NC15 Criteria is achieved meanwhile the exterior noise can be 90 dBA. Exhibitions rooms were another challenge. They are huge, without any inner partitions and with a minimalistic aesthetics. The reverberation control was difficult to achieve but a special ceiling finishing gives a perfect acoustic comfort to the visitors. The building also hosts a service of restoration, collect and research.