Dual 21" Subwoofer

Large format Dual 21" Active Touring subwoofer with truly professional finish, materials equivalent size and cost to conventional dual 18", with 50% more output power and fast accurate response even at high crossovers, for any touring or high SPL or infra extension subwoofer application.


BASSO2121-A is classic design dual 21″ Direct Radiation subwoofer that meets all the expectations for Touring and large venues and High-SPL applications.

This active subwoofer features an integrated amp module capable of handling up to 4 kW and provides a linear response typical of subwoofers with both deep low frequency response and excellent impulse and transient definition. Thanks to a carefully designed and tuned cabinet and eight symmetrical front-firing ports that allow for extremely linear excursion of woofers, maximizing their SPL response and minimizing mechanical noises and distortion.

A high-end 24bit @ 48kHz AD/DA integrated DSP board allows for quick and precise adjustments thanks to advanced limiters and FIR filters and 4 selectable Set-up presets.

Like All IDEA Loudspeakers BASSO2121-A is built with the necessary structural strength and finish quality required for durable touring use. The high quality 18 mm birch plywood enclosure coated with IDEA Aquaforce custom paint solution and a 2-mm steel front grille.


  • Compact Dual 21˝ Direct Radiations design
  • Rugged and durable 18 mm birch plywood construction and finish
  • Premium European High Efficiency custom IDEA Transducers
  • 4 kW Class-D Amp
  • XLR and PowerCON connectors
  • Durable Aquaforce paint, available in standard textured black or white, optional RAL colors (on demand)
  • 36 mm pole cup and four integrated handles


  • Main system for Regional Touring and Rental Companies
  • FOH for high SPL venues and clubs


Enclosure design Bass Reflex
Transducers 2 × 21″
Class D Amp Continuous Power 4 kW
DSP 24bit @ 48kHz AD/DA
4 selectable active LPF cuts
SPL (Continuous/Peak) 136/142 dB SPL
Frequency Range (-10 dB) 20 – 80/95/120 Hz
Frequency Range (-3 dB) 24 – 60/75/100 Hz
Dimensions (W×H×D) 1200 × 600 × 950 mm
Weight 131 kg
Audio Signal Connectors
AC Connectors 2 × Neutrik PowerCON® (I/O)
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 4 skates (H/V)
Installation 36 mm Pole mount socket
Accessories 35 mm Pole (P-21336)
Wheels (WH-04)


* Specifications may be subject to change without notice.


Spare Parts

  • S21-41-8 | Woofer 21″
  • R-S21-41-8 | Membrane for woofer 21″
  • AMP-DIGIMOD-3004PFC4 | Power Module
  • HSL-01 | Heat Sink Large
  • PM-DIGIMOD3004-PC4 (Power module + interface + DSP LITE + Heatsink)