The U21 is where the UNO series steps into serious low-frequency territory. Designed for large rooms and high-output systems, it delivers deep, controlled bass with the precision and consistency Procella is known for. It’s not just about moving air; it’s about controlling it. The U21 keeps every hit tight, every rumble defined, even at high SPL. No excess, no blur. Just low-frequency performance that stays locked into the mix, exactly as intended. For systems that demand more headroom, more depth, and more authority, the U21 brings the foundation in line with the rest of the experience.Part of the UNO series. Built to keep up when everything else scales. Specification Details Impedance 8 Ohms nominal Frequency Response -3 dB at 21 Hz Power Handling Continuous 1800W / Peak 3600W Maximum SPL Continuous 124.7 dB / Peak 127.4 dB Components Professional 21” driver, 4.5” voice coil, neodymium magnet, 110 litre sealed enclosure Connectivity Gold plated binding posts Amplifier External, sold separately; 2-ch bridge DA08-DSP Construction Internally heavily braced MDF, semi-matte textured black lacquer Dimensions & Weight 805 × 700 × 290 mm (300 mm with grille), 48 kg Shipping Carton 803 × 908 × 375 mm, 52 kg Included Installation guide Assembly Belgium, 100% QC testing
