The high-performance IGx subwoofer, with integrated push-pull drive in conjunction with its geometrically optimised enclosure and advanced carbon fibre polyethylene-terephthalate cone, is capable of reproducing live timpani, kick drums and kettledrums. Weighing only 100g, the carbon fibre polyethylene-terephthalate membrane is geometrically optimised and made from a woven material that contains both the fibre and the resin matrix. This material is woven exclusively in Europe for Wilson Benesch and sets the industry standard for both stiffness and damping.
Inspired by the instruments it is designed to reproduce, the circular outer structure of the IGx is the geometrically perfect shape to effectively counteract any kind of resonance. A conventional dynamic driver places a membrane in a cabinet with a moving coil connected to a stiff spider in the centre of the cabinet structure, which controls the position of the membrane with a rubber surround connected to the cabinet perimeter. In opposite, the IGx has no basket at all. During playback, the position of the lightweight cone is determined and controlled by two 82 mm moving coils and two high-performance NdFeB magnets working in a push-pull formation.



An exclusive carbon fibre PET membrane

A completely unique carbon fibre PET mesh was developed by Wilson Benesch during the development of the original Torus infrasound generator. This mesh is woven exclusively for WB in Europe and allows the complex, highly optimised torus geometry of the IGx membrane to be formed from a single piece of mesh, providing maximum stiffness with maximum damping.

The IGx 18" membrane is the stiffest, lightest and best damped dynamic drive unit membrane ever made. It weighs less than 100g but is able to carry a thousand times its own mass - a testament to the stiffness of the structure.

The Core

The dual motor push/pull drive system consists of two sets of 82mm diameter voice coils positioned in front of and behind an 18-inch CF PET woofer cone around a massive 16kg precision machined central core. The core dissipates all heat and structurally induced resonant energy directly to the floor, bypassing the cabinet.

Horizontal and vertical struts

The IGx has a geometrically optimised, circular drum shape. This ensures maximum rigidity across the entire outer structure. Furthermore, Wilson Benesch has equipped the IGx with additional rigidity and damping in the horizontal and vertical axis of the IGx. A steel ring in the horizontal axis and steel rods in the vertical axis provide additional stiffness and damping.

The result is a highly inert, acoustically quiet, drum-shaped enclosure that eliminates a common problem with subwoofer designs.

Efficient class D amplification

The IGx is powered by a powerful digital amplifier. In addition to almost limitless power, high efficiency and low heat generation, it benefits from an ultra-compact design and high reliability.

Class D amplification has developed rapidly in recent years. The quality of this amplifier technology today far exceeds the possibilities that existed when the Torus was developed.


Driver technology
  • Membrane material: 18” carbon fibre - Polyethylene Terephthalate (PET)
  • Large steel core with 2x voice coils, 2x NdFeB high-performance magnets in push-pull formation
Outout power
  • 100W Continuous power
  • 500W Max in 4Ω
Frequency response
  • 12Hz to 90Hz Max (-3dB)
  • 12Hz to 30Hz Min (-3dB)
Input impedance
  • 10k ohms (RCA)
  • 10k ohms per phase (XLR)
  • 180k ohms (Speakon)
Distortion (THD)
  • < 0.04% @1W
Phase shift
  • Balanced passive all-pass filter (0°-deg to 180°)
Phase shift bypass
  • Panel-mounted toggle switch (direct or variable phase)
Analogue Inputs
  • 1 x left RCA 1 x left XLR
  • 1 x right RCA
  • 1 x right XLR
  • 1 x left & right high level Speakon
Input sensitivity
  • 500mV (low level unbalanced RCA)
  • 250mV per phase (low level balanced XLR)
  • 5V (high level Speakon)
Power consumption
  • 10W-15W (idle), 650W maximum
  • Height 432mm (17”) incl. spikes
  • Diameter 510mm (20")
  • Depth 368mm (14.48”)
  • Weight 54kg (119lbs)
  • Weight of the magnetic grid 3kg (6.6lbs)