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Sound absorption panel placement often focuses primarily on walls and ceilings. But sound waves in your room don’t just bounce predictably from floor to ceiling and between walls. Low-mid frequencies can get trapped in the corners of your room, creating a “boomy” effect that will be evident during playback.

Primacoustic’s Cumulus Tri-Corner Bass Trap helps eliminate this boominess, simply and efficiently. Made from high-density glass wool, the Cumulus Tri-Corner Bass Trap creates a 17″ deep air cavity in room corners. The result is high-quality broadband sound absorption, taming problematic resonances in the low-mid region.


Product Variations





24 × 24 in (610 × 610 mm)


SKU Edge Thickness Finish Box Qty Surface Area Coverage (per box)
Z840-1210-03 Reverse Beveled 2" (51mm) Fabric 2 3.5 sq ft (0.3 sq m)
Z840-1210-00 Reverse Beveled 2" (51mm) Fabric 2 3.5 sq ft (0.3 sq m)
Z840-1210-08 Reverse Beveled 2" (51mm) Fabric 2 3.5 sq ft (0.3 sq m)

Mounting Hardware included

Mounting the Cumulus

The difficulty of mounting a panel in the top corners of a room will often deter people from taking advantage of this important room location. The Primacoustic Cumulus’s ingenious mounting hardware – comprising spring-tensioned clasps and a single eye-screw – makes installation easy. Mounting literally takes minutes and the Cumulus’s reverse beveled edges flush mount ‘seamlessly’ into the corner. The deep air space cavity behind the panel increases the low-mid absorption characteristics while leaving the architectural design of the room virtually intact.

Cumulus Extra Diagram1a

Cumulus Extra Diagram2a


Critical Listening Accolade

Critical Listening

Glass wool panels are the industry standard acoustic treatment for critical listening, for use in rooms where audio fidelity really matters. Their superior absorption qualities are perfect for controlling all broadband and bass frequencies.


Fire Rated

Primacoustic Panels are fire rated to be safe to use in any environment.



LEED provides a framework for healthy, efficient, carbon and cost-saving green buildings. LEED certification is a globally recognized symbol of sustainability achievement and leadership.

Essential Information


  • Core Panel Material: Glass wool
  • Finish: Acoustically transparent Polyester fabric
  • Weight: 1.4 lbs (0.6 kg)
Content  2

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