Back to series Quantum 750


Quantum 731 A

Active subwoofer, bass reflex, downfire


  • Home cinema bass: Subwoofer for the Quantum 750 range
  • Punchy, dynamic bass reproduction for music and film
  • 300 mm long-excursion downfire subwoofer for precise and powerful deep bass
  • High-performance amplifier with a maximum power output of 360 watts
  • Extremely low-resonance, solidly built enclosure with a multiple braced body


Active subwoofer, bass reflex, downfire


The Quantum 731A is the perfect low-bass counterpart to the Quantum 750 series. Besides the extremely low-resonance 45 mm case front on a corpus with multiple stiffening, it offers a clear and modern language of shape that is available in perfect high-gloss or silk-matt varnish finishes. The latest-generation computer-optimised long-throw subwoofer chassis delivers uncompromisingly clean and dynamic basses.


The Quantum 731A is available in a black, white or black-mocha finish. A long-throw subwoofer chassis with a diameter of 300 mm and hardened paper cone, high-strength die-cast basket and ventilated high-performance voice coil is responsible for ideal bass precision. The high-gloss base plate maintains a defined distance to the chassis for optimum level efficiency, the high-performance power amplifier guarantees highest level reserves.

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