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SMS-HDN Hidden In-Ceiling Sound Masking Speaker

The SMS-HDN speaker mounts out of sight behind suspended tiles or gypsum drop ceilings, turning the ceiling itself into a large, diffuse sound masking speaker. It delivers uniform masking, clear paging, and music with no visible hardware, no acoustic hot spots, and controlled sound leakage between adjacent private offices.

  • Hidden behind ceiling tiles or gypsum, leaving the ceiling clean
  • Turns the ceiling into a large, diffuse source with no hot spots
  • Independent per-office volume control prevents sound masking leakage between adjacent rooms through the open plenum
  • Low-profile vibration exciter at just 0.47 kg
  • Sliding switch trims output 0 to -6 dB in 1.5 dB steps
  • UL 2043 plenum-rated; bonds in place with construction adhesive or its dedicated preconstruction mounting bracket
Specifications
Power5 W
Line voltage25 V
Enclosure materialFireproof Lexan (UL 94-V0)
Frequency response100 Hz to 10 kHz
Output level70 dBA (typical, on gypsum board)
ConnectorsScrew-on
DriverVibration exciter
Level adjustmentSliding switch, 0 to -6 dB in 1.5 dB steps
Max speakers per channel4 (ML-SL), 6 (RL96 / CMS-II)
CertificationUL 2043, UL 62368
MountingConstruction adhesive or dedicated steel mounting bracket
ColorWhite (RAL 9016)
Weight0.47 kg (1.0 lb)
Shipping weight0.55 kg (1.2 lb)
Dimensions18 × 14.8 × 5.5 cm (7 × 5⅞ × 2⅛")
SMS-HDN dimensions drawing
Box dimensions21.5 × 17 × 8 cm (8½ × 6¾ × 3⅛")

Resources

Spec sheet User manual 3D models
HDN hidden in-ceiling sound masking speaker
HDN hidden in-ceiling sound masking speaker
HDN hidden in-ceiling sound masking speaker
HDN hidden in-ceiling sound masking speaker

Specify & Install Sound Masking With Confidence

From system design guidelines to installation manuals and technical drawings, our documentation gives specifiers, integrators, and facility teams everything they need to deploy Soft dB sound masking correctly.

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Traditional systems raise and lower masking on a fixed timer, guessing at how busy a space will be. Adaptive sound masking measures the real ambient noise and adjusts continuously, so speech privacy and comfort stay consistent whether the floor is packed or empty, with no one touching a dial.

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