FAQ – Distributed Audio

  1. What is sound masking? Sound masking is an extensive topic; textbooks provide in-depth information on the subject. In brief, a sound masking system is most commonly used in an open office environment (an area with low partitions or cubicles) to provide a degree of conversational privacy by adding background noise and shaping the signal to mask speech. Masking conversational noise can also contribute to improved productivity. In a sound masking system, the audio signal is fed from a noise generator to an amplifier and then to the sound-masking speakers that are positioned out of view, usually above ceiling tiles in what is commonly called the plenum area.
  2. Why should I use a backbox? Local building codes may require a backbox, especially when installed in a return air plenum space. A backbox can also protect the speaker from falling debris and dust.
  3. How do you stop speaker hums/buzzes? Read the white paper on Eliminating Ground Loops.
  4. Does Lowell have a fire-rated speaker system? Lowell does not offer fire-rated speaker systems at the present time.
  5. Does Lowell have a speaker that can be used with a fire alarm system?Lowell does not offer speaker systems with the required Fire Alarm System or a Mass Notification System listing at the present time.
  6. Does Lowell have a speaker and/or backbox that is plenum rated? A component (speaker or backbox) cannot be plenum rated. A speaker system can be plenum rated if it has been evaluated by a third party laboratory — such as Underwriters Laboratories (UL Listed) or Intertek (ETL Listed) — and meets the standards for the UL 2043 test for visible smoke release. The enclosure would have a sticker stating that it meets the UL 2043 standard. The sticker would also list the components (speaker, transformer, grille) that would be required to make the speaker system complete and therefore the classification valid.
  7. Is a safety cable recommended when suspending iMount® speakers? Lowell recommends that a safety cable be used anytime speakers are installed in an open space above an area where people could be present. The safety cable should be able to suspend the entire weight of the speaker system in the event the primary rigging system fails.
  8. Does Lowell provide speaker rigging design assistance? Lowell does not provide engineering assistance in rigging system design, which is the responsibility of the installing contractor, and strongly recommends that any rigging system for loudspeakers be reviewed and approved by a certified structural engineer before speakers are installed.
  9. Does Lowell provide speaker system design assistance? Lowell engineers can offer recommendations on the suitability of Lowell products for specific applications; however, the speaker system design is solely the responsibility of the installing contractor or consultant.
  10. Does Lowell make custom audio products? Yes, Lowell can provide a quotation for a custom product configured using our standard components. Contact sales@lowellmfg.com for information.
  11. Are Lowell speakers available in other colors? A variety of custom colors are available for some speakers. Additional charges and extended delivery times would apply. Contact sales@lowellmfg.com.
  12. Do LT Series speakers require an earthquake support cable to structure or hardware to attach the speaker to the ceiling tile grid? Earthquake codes vary by geographic location. Contact your local building inspector for information.
  13. Can Lowell’s  OS Series (indoor/outdoor speakers) be installed with hardware other than the included U-bracket? Lowell OS-50 and OS-100 series speakers feature threaded insert points on the rear, so they can be installed with Lowell’s optional omni-directional bracket (OS-BRKT-B/W) or with Adaptive Technologies Group bracket (MM-008-BT, by others). Lowell’s OS-150 series speakers also feature threaded insert points on the rear and can be installed with several different load-rated commercially available speaker mounting brackets, such as some made by Adaptive Technologies Group or Omnimount.  Verify the mounting bolt pattern alignment (shown on the speaker specification sheet) and the weight load rating (from the bracket manufacturer) before using their bracket to mount them.
  14. Does Lowell have a paging horn that can be installed in a return air plenum space?  Yes, Lowell models LUH-15TA and LUH-15TX are listed for UL 1480A General Signaling and are rated for UL 2043, making them suitable for use in a return air plenum space.
  15. Are attenuators continuous rotation? No. Although Lowell attenuators were originally designed to provide continuous rotation, changing preferences over the years fostered a design that does not turn all the way around.
  16. What kind of speaker wire should I use?  The sound system speaker cable choice depends heavily on the electronic design of the sound systemʼs amplifier equipment and not just the speaker itself. More
  17. Can you use a 25V speaker transformer on a 70V amplifier system (or 70V speaker transformer on a 25V amplifier system)? Lowell Manufacturing does not recommend using a speaker matching transformer that is not rated for the output voltage of the amplifier being used. More
  18. Does Lowell offer a speaker volume control that doesn’t turn completely OFF when turned to zero? No, but a modification can be made when wiring the volume control (attenuator) that will provide a preset minimum volume. It involves adding a 1-watt resistor to the common (–) leg of the volume control wiring. The 1-watt resistor value is from 100 to 1,000 ohms. The higher the value of the resistance added, the higher the minimum volume will be. Experiment to determine the resistor value that works best for the application (wiring drawing).