Cambridge Sound Qt® E-P-B-30-4 Active emitters for sound masking, paging & music (Black) 4 Pack - 911.0898.900

Product Overview

The Cambridge Sound Qt E-P-B-30-4 (part number 911.0898.900) is a 4-pack of black Qt Active Emitters for sound masking with simultaneous paging and background music reproduction. Each emitter is a compact, ported, direct-field loudspeaker with active electronics that delivers 17 dB more output than previous direct-field emitters. The units are plenum rated, UL 2043 compliant, and nearly invisible once installed in finished or open-structure ceilings. They connect over standard category UTP cabling with RJ-45 connections.

Product Description

Conventional masking systems bounce sound off the ceiling deck from large upward-firing loudspeakers; the Qt Active Emitter instead projects the masking signal directly into the workspace using Cambridge Sound's direct-field Quiet Technology, producing uniform coverage without relying on the plenum as a mixing chamber. Direct-field delivery also improves paging intelligibility and music quality, since the driver faces the listener rather than playing through ceiling material — making this the single-source emitter that handles masking, paging, and music together. The ported enclosure extends low-frequency response down to the 125 Hz octave band for masking and 115 Hz for paging and music, with masking output adjustable from 30 to 60 dBA at 1 meter and paging/music peaks up to 74 dBA. Four uncorrelated audio channels auto-sequence across emitters to reduce phasing and comb-filtering. Rear DIP switches attenuate individual emitters by up to 4.5 dB in 1.5 dB steps, and a slip-ring mount for acoustical tile ceilings is included. The emitters are compatible with Qt 300 and Qt 600 control modules and with the DynasoundPro network system (specify DS1320), using the same cabling infrastructure as the rest of the QtPro platform. See controllers and accessories in the Cambridge Sound collection.

Key Features

• Masking, Paging, and Music — one emitter reproduces all three signals from a single source.
• Direct-Field Quiet Technology — projects masking into the workspace for uniform coverage.
• 17 dB More Output — louder than previous direct-field emitter offerings.
• Extended Low Frequency — ported enclosure reaches the 125 Hz octave band for masking, 115 Hz for paging/music.
• Plenum Rated — UL-listed and compliant with UL 2043 for air handling spaces.
• Four Uncorrelated Channels — auto-sequencing channels reduce phasing and comb-filtering.
• Per-Emitter Attenuation — rear DIP switches trim up to 4.5 dB in 1.5 dB increments.
• Simple RJ-45 Cabling — standard category UTP (8-conductor) infrastructure.
• Tile-Ceiling Mount Included — slip-ring mount for acoustical ceiling tile installation.
• Broad Compatibility — works with Qt 300 and Qt 600 control modules and the DynasoundPro network system (DS1320).

Typical Applications

• Open offices — uniform masking with clear overhead paging and background music.
• Private offices and conference rooms — discreet ceiling emitters protect conversation privacy.
• Healthcare facilities — speech privacy and paging in clinics and patient areas.
• Call centers — reduces agent-to-agent distraction while supporting floor paging.
• Financial and legal offices — confidential client discussions stay private.

Technical Specifications

Specifications sourced from Cambridge Sound vendor data. Unlisted values are omitted rather than estimated.

FAQ

Can one emitter handle masking, paging, and music at the same time?
Yes. The Qt Active Emitter reproduces the masking signal and paging/music audio simultaneously from a single source.

Which control modules work with these emitters?
The Qt 300 and Qt 600 control modules, and the DynasoundPro network system (specify DS1320 for that platform).

Are they safe to install in the ceiling plenum?
Yes. The emitters are plenum rated, UL listed, and comply with UL 2043 for air handling spaces.

How is per-emitter volume adjusted?
Rear DIP switches attenuate each emitter by 0, -1.5, -3, or -4.5 dB, in addition to system-level zone control.

What cabling do they use?
Standard category UTP (8-conductor) cable with RJ-45 connections, the same infrastructure used across the QtPro platform.