Sonus Faber Grand Piano Concerto Speakers Very Good Condition. The Grand Piano is the top of Sonus Faber's affordable Concerto series (see Martin Colloms' review of the Concerto in the January 1998 Stereophile), and the company's first and only floorstanding speaker. According to Sonus Faber's product literature, a love of violin making inspired the woodworking excellence—and not merely for its physical beauty. Rather, the company sees the speaker baffle as an instrument which amplifies sound, not merely a container of sonic power with technically approved Description: Two-way, floorstanding loudspeaker: Drive-units: ¾ silk-dome tweeter, 7 acrylic-treated paper-cone woofer, 7 acrylate/carbonium-cone passive radiator. Crossover Frequency: 2.3kHz. Frequency response: 40Hz-20kHz, ±3dB. Impedance: 8 ohms nominal. Sensitivity: 87dB/1W/1m. Power requirements: 30-200W. Dimensions: 39½ H by 9½ W by 11½ D. Weight: 60 lbs each. Serial number of units reviewed: 752 (both). Manufacturer: Sonus Faber, 36057 Arcugnano (Vi), Italy.