21” Passive Band-Pass Subwoofer

Created for ultimate electro acoustical performance, BASSO21t delivers very high SPL levels and efficiency in a medium format enclosure. Applications have a very wide range of possibilities, since it can be chosen to be "the sub" of portable, regional touring or installed solutions with limited budget, or extreme SPL solutions for touring or club installations that combine arrangements multiple units.


Many key factors are to be considered when configuring the subwoofer section of a loudspeaker system to perfectly match each application: size/weight, logistic and operational setups, SPL needs, LF extension, cost limitations, as well as sound engineer preferences (depending on different the type and size of the event) or audio program characteristics and regional style taste for subwoofer mixes.
BASSO Series models allow the user to choose the most adequate subwoofer for any given situation from within a family of products with common finish, design solutions and performance philosophy as well as shared rigging and transport accessories.
BASSO21t is a 21″ subwoofer that has been designed to deliver high SPL levels and efficiency out of a medium format enclosure delivering serious power density.
The 5th Order Band-Pass design together with the premium-quality European 21″ woofer deliver serious SPL with maximum impact in the 50 to 100 Hz octave and the extended sub range of 30 Hz allows for Infra extension application into any system.
BASSO21t features four integrated handles and two 35 mm pole mount sockets for vertical and horizontal set-ups.BASSO21t is compatible with optional BASSO rigging frames for ground-stacked configurations. Optional wheels kit is also available.


  • High output 5th order Band-Pass design
  • Premium European High Efficiency custom IDEA 21″ transducer
  • Dual Neutrik NL4 connectors
  • 8 Ohm Passive
  • Rugged and durable 18 mm birch plywood construction and finish
  • Durable paint coating process, available in standard textured black or white
  • Optional RAL colors (on demand)
  • Four integrated handles and two 36 mm pole cups (V/H)
  • Compatible rigging accessories (optional) for stacked and flown configurations with VOA systems


  • High SPL A/V, portable professional sound reinforcement and touring
  • Flown subwoofer in fixed installations for concert venues and sports arenas
  • Main or distributed subwoofer system in Pubs, Lounges, Bars and clubs
  • “Infra” extension for BASSO Series LF sections
  • Broadcast Studios and Screening rooms
Enclosure design Band-Pass
Transducers 1 × 21”
Power Handling (RMS) 1400 W
Nominal Impedance 8 Ohm
SPL (Continuous/Peak) 132/138 dB SPL
Frequency Range (-10 dB) 25 – 100/120/150 Hz
Frequency Range (-3 dB) 30 – 80/100/120 Hz
Dimensions (WxHxD) 900 x 600 x 950 mm
(35.4 x 23.6 x 37.4 inch)
Weight 81 kg (178,5 lbs)
2 x Neutrik speakOn NL-4 in parallel
Cabinet Construction 18 mm Plywood
Grille 2 mm perforated weatherised steel with protective foam
Finish Durable IDEA proprietary Aquaforce paint coating process
Handles 4 integrated handles
Feet/Skates 2 skates (H)
Installation Two 36 mm Pole mount sockets (top and side)
Accessories Riggin Frame (RF-900)
Riggin Frame adaptor (RF-9060)
Riggin System (RS-BASSO-L)
Casters (WH-04)
35 mm Pole (P-21336)

* Specifications may be subject to change without notice.