• Sound Masking’s Invisible Goal

    September 13, 2018

  • Jim Tchinski, EET, CTS, NET+, NICET
    Solutions Engineer

    It’s another day at the office. You come in and try to get as much done in a day as you can, with interruptions of course. Co-workers and customer interruptions are expected. That’s part of the day. It’s all the other chatter around the office that reduces your concentration. Wouldn’t it help to have something to improve it during the day?

    You’re at the doctor’s office in an exam room. The doctor is in the room next to you with a patient and you can hear everything about their problems whether you want to or not. This is not the privacy that is required in a clinical environment. Shouldn’t something be there to stop this problem?

    Both situations listed above have the problem of speech being too easy for the human ear to pick up. What can be done to help this? We can’t build thicker walls, as the buildings are already there and we can’t keep all office doors closed if there even are doors. This is where a sound masking solution comes into play (commonly mis-referenced as a white noise system). I will not go all “sound guy” here but I would like to give a basic explanation of the differences on why sound masking works.

    • White noise is the same volume for all frequencies.
    • Pink noise volume decreases as the frequencies raise and covers all frequencies.
    • Human speech is only in a specific frequency range and the volume is higher at lower frequencies and then the volume falls off rapidly as frequencies increase.

    The noise generated by a properly-tuned sound masking system will mimic human speech frequencies and volume levels. The purpose of this is so that it sounds natural to us and it helps “mask” other speech patterns in the area by actually raising the noise in the area. Just using straight white noise or pink noise could just cause irritation. Please note that sound masking does not eliminate other sounds, it mainly reduces the intelligibility of other speech in the area making it more difficult to understand so it turns into background noise.

    Now that the “sound guy” is off the podium, let’s go back to what we can do for offices and exam rooms. First, we need to determine where the problems are and what noise we need to make less intelligible. In the office area, there are open offices and people talking in the halls. In this situation we could install speakers that would cover the halls and the offices so that speech intelligibility is reduced in all areas. In exam room areas, the main problem is “room to room”. We can then focus on just having sound masking in the rooms but not in the halls. This would raise the noise levels in the rooms causing the speech from other rooms to be less intelligible.

    In both of these situations the goal of effective sound masking would be to install a system that is not noticed. One that runs in the background 24-hours a day, at a consistent level and remains invisible to the occupants. Does your facility need a sound masking? Contact ESCO Communications today and learn more by visiting our AV Integration Solutions.