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SMS-STX Open Ceiling & Plenum Up-Firing Sound Masking Speaker

The SMS-STX speaker delivers the same soft, diffuse up-firing sound masking as the SMS-STR in a footprint about 40% smaller and 35% lighter. Built for plenum and open-ceiling spaces, it spreads a uniform broadband masking sound throughout the space while keeping wiring effort and visual impact to a minimum.

  • Matches the SMS-STR's acoustic performance and uniformity in a much smaller, lighter package
  • Up-firing design keeps sound masking signal diffuse and smooth, with no dead or hot spots
  • Lightweight, durable Lexan polycarbonate shell
  • Phoenix screw connector blocks for clean, error-free wiring
  • Optional SMS-STXATT plug-in attenuator makes it possible to drop individual speaker output by 3 dB or 6 dB
  • UL 2043 plenum-rated; ships in boxes of 12 for faster rollout
Specifications
Power10 W
Impedance75 Ohms
Line voltage25 V
Sensitivity92 dB
Enclosure materialLexan polycarbonate
Frequency response100 Hz to 10 kHz
ConnectorsPhoenix screw connector
Driver11 cm (4.5") full range
ColorWhite (RAL 9016)
Anchor device5 mm plastic hook at the center
Seismic securityExtra 5 mm plastic hook
Speaker attenuation3 dB / 6 dB with external SMS-STXATT (sold separately)
CertificationUL 2043, UL 62368, CE
Weight1.26 kg (2.8 lb)
Shipping weight1.4 kg (3.1 lb) each, boxes of 12
DimensionsØ 17.2 cm top / 16.7 cm base × 10 cm H (Ø 6¾ / 6 9/16 × 3 15/16")
SMS-STX dimensions drawing
Box dimensions59 × 41 × 26 cm (23¼ × 16¼ × 10¼"), boxes of 12

Resources

Spec sheet User manual 3D models
STX up-firing open ceiling and plenum sound masking speaker
STX up-firing open ceiling and plenum sound masking speaker
STX up-firing open ceiling and plenum sound masking speaker
STX up-firing open ceiling and plenum sound masking speaker

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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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