Crosstalk Silencer for Return Air Grilles
Blocks noise traveling through open return air grilles.
Two models: Standard G2 (Speech specific) and Septum G2 (equipment noise and speech)
The G2 Plenum Return Silencer is a crosstalk silencer for open return air grilles. It mounts in the plenum above a standard 2×2 or 2×4 ceiling grid and blocks speech passing through the return while allowing return airflow. Two models: Standard G2 for speech, Septum G2 for speech plus equipment noise.
Send your room dimensions, plenum height, ceiling grid size, lighting fixture counts and return grille counts. We return a system layout and a quote at no charge.
Before you specify
Check your plenum height. The recommended minimum plenum height is 24 inches. Where the plenum is shallower, the vertical hood supports can be trimmed, and the installation guide covers how far. If there is an obstruction directly above a return grille, the usual answer is to move the silencer to a nearby grille with clear plenum space above it.
Sizes and specifications
- Sizes available for 2×2 or 2×4 ceiling grid systems
- Standard G2 item #3142, Septum G2 item #3542
- Hood: 31″w x 9″h x 1″t (787 x 229 x 25 mm)
- Chute: 18″h x 1/2″t, trimmed height 14″ (457 x 13 mm, trimmed 356 mm)
- Mat: 24″ x 24″ x 1/2″t (610 x 610 x 13 mm)
- Standard G2 15 lb, G2 with 1 lb plenum 24 lb
- Recommended minimum plenum height 24″
- Specification section CSI 23 32 48.11, Acoustic Air Plenum Accessory
Construction
Thermally molded fiberglass chute and hood, made in the USA with recycled materials. The finish is black non woven polyester. The air stream side of the chute carries a black fiberglass mat over a core of glass fibers bonded with a thermosetting resin, with a fire resistant foil scrim on the exterior extending the full width of the chute. The chute section has four 2″ x 2″ stanchions that support the hood, and the hood attaches where the four stanchions meet.
Performance data
Airflow. Maximum 750 CFM.
Surface burning. The Spirit Acoustics literature states a Class A rating per ASTM E84, with a maximum flame spread index of 25 and maximum smoke development of 50, referenced to UL 723, to NFPA 90A and 90B, and to CAN/ULC S102-M88 in Canada.
Operating limits. Maximum operating temperature 250°F (121°C) per ASTM C411. Maximum internal pressure 2″ w.c. (498 Pa) per UL 181.
Resistance. Does not breed or promote fungi per ASTM C1338. No growth per ASTM G21 (fungi) or ASTM G22 (bacteria). Water vapor transmission under 0.02 perms per ASTM E96. Water vapor sorption under 5% by weight per ASTM C1104.
- Integrates into standard 2 x 2 or 2 x 4 ceiling systems
- Application-specific engineering and design
- Easily assembled and installed
