Buying Guide・2020-07-23
Caution! Don't let covered courts become "risk" courts that damage children's hearing!
Industry Insights
In recent years, "semi-outdoor sports courts" or "sheltered playgrounds" have become highly acclaimed facilities in schools of all levels. On sunny days, they provide shade to avoid direct sun exposure and reduce the chance of heatstroke among students; on rainy days, they shelter from wind and rain, ensuring uninterrupted learning. Meanwhile, in recent years, many schools have utilized the roofs to install solar panels, building one after another
providing shade and rain protection for students while achieving energy saving and environmental protection
triple-win facility.
What is a covered court?
The venue for school activities on rainy days is called a covered playground. Since building an indoor gymnasium or indoor comprehensive court requires a huge budget, which not all schools can afford, most schools make good use of their existing space to set up a rainy-day activity area for students, commonly referred to as a covered playground. Most existing school covered playgrounds utilize basements, rain shelters built between two classroom buildings, or indoor activity spaces created by connecting several classrooms, planned as simple basketball, badminton, or tennis courts.
(Source: National Academy for Educational Research_Covered Playground)
However, such well-intentioned facilities may become "noise"—a risk factor that harms school children's hearing—due to poor PA system engineering planning. Noise lurks in every corner of the campus but is often ignored. If students are exposed to a noisy environment for a long time, it can affect their learning at best, and damage school-age children's hearing at worst, causing permanent hearing loss.
When general system integrators encounter projects like covered courts, most would immediately think of installing outdoor horn speakers. However, they inadvertently build a hazard on campus that can damage children's hearing.
Why are horn speakers not suitable for covered playgrounds?
The biggest advantage of horn speakers commonly seen outdoors is that in open outdoor spaces, the sound can be very loud and travel far. However, when encountering "semi-outdoor" scenarios like covered courts, the roof, surrounding steel beams, and concrete pillars will cause sound wave refraction and reverberation.
, resulting in no sound output.
When the sound is not coming through, operators subconsciously turn up the volume. Once the volume is increased, it causes excessive sound pressure
, it will cause pressure on human hearing, resulting in discomfort. If the volume is increased further, it will produce an unbearable "oh~ oh~ oh~" reverberation noise and sound pressure, which can cause hearing damage in children.
PA system solutions suitable for complex scenarios
In the project of Guanghua Elementary School in Kaohsiung City, Jerry Hung, General Manager of BXB Electronics, saw that Guanghua Elementary School had such a great venue but lacked a complete sound reinforcement system and planning. Therefore, he dispatched engineers to inspect the school and proposed an improvement plan to the principal using column speakers for sound reinforcement.
In the application scenario of semi-outdoor covered playgrounds, using column speakers has several advantages:
The vertical sound control effect of column speakers is excellent. In environments with severe reverberation or refraction, it can effectively concentrate and transmit sound to the audience, reducing reflection after hitting the walls.
situation.
Column speakers can keep the sound pressure level moderate and equidistant, allowing
People both locally and remotely can hear clearly at the same time
. It is the best solution to achieve excellent sound reinforcement in semi-outdoor and acoustically complex environments while protecting children's hearing.
Column speaker sound field diagram: Column speakers have extremely strong control over vertical sound coverage, featuring narrow vertical coverage that reduces resonance between the sound and the ceiling or stage, allowing listeners to obtain more direct and clear sound.
BXB proposed a PA system and the brand-new WS Series waterproof column speakers for Guanghua Elementary School
。
This waterproof column speaker is IP55 certified, meeting outdoor waterproof requirements as a baseline. Its greatest features lie in its maximum sound pressure level of 105dB, dispersion angle of 180°/150°, and frequency response of 110Hz ~ 20KHz.
BXB WS Series Waterproof Column Speakers
The noise decibel we often refer to is professionally termed "sound pressure level," generally expressed in decibels (dB), which refers to the pressure exerted by sound waves on our eardrums. For the human ear, hearing 120dB usually causes ear pain. And
Prolonged exposure to an 80 dB environment poses a risk of hearing loss
, which is cumulative and irreversible. Therefore, we should always pay attention to whether the sound pressure level of surrounding noise is too high, posing a risk of hearing damage.
BXB's waterproof column speaker features a maximum sound pressure level of 105dB, designed to
Completely avoid the risk of hearing damage caused by excessive sound pressure levels
. Its 180-degree horizontal dispersion and 150-degree vertical dispersion make it the ideal configuration for semi-outdoor scenarios like covered playgrounds, ensuring clear hearing without the need to constantly increase the volume.
For students, especially school-aged children, "harmony" of sound is best for developing hearing. Fluctuations in the frequency response curve represent differences in the gain of the audio equipment for sound signals in different frequency bands.
110Hz~20KHz frequency response
, the volume ratio of high, mid, and low frequencies when listening to a song or broadcast will be more harmonious, and the volume level of each frequency band is moderate, making it the most suitable sound for the campus.
In addition to product selection, the most critical "know-how" is... how to layout and install the appropriate sound reinforcement equipment once selected
is what determines the success or failure of the entire project. Different spaces and architectural structures will affect the transmission of sound energy. For example, the larger the space, the poorer the uniformity of sound transmission. An uneven layout also limits the gain of sound transmission, so users usually turn up the volume higher and higher. This leads to excessive sound pressure in seating areas closer to the speakers, while the middle seating areas receive sound from too many directions, which actually reduces speech intelligibility.
The layout of sound reinforcement systems is a highly experience-dependent technical task
. In the case of the covered playground at Guanghua Elementary School, it is an array formed by dozens of column speakers. The adjustment of the up, down, left, and right angles of each column speaker is the accumulation of decades of experience. During the construction acceptance, General Manager Hung personally walked to every corner of the court to test and listen to the sound emitted by the newly installed sound reinforcement system, checking for abnormal echoes and whether the volume in each area was uniform and moderate. He then asked the technicians to adjust the speakers one by one to ensure that in every space of the covered playground, the sound was stress-free for the students' ears and could be heard clearly.
Creating a risk-free learning environment
The campus should be a healthy and happy teaching and learning environment for teachers and students. When building novel facilities, we can think a bit more about whether anything has been overlooked and whether it might pose potential health risks. Noise is a hazard factor that is easily overlooked. BXB Electronics provides products and solutions designed with the care of teachers and students in mind, working hand in hand with you to create a risk-free and comfortable learning environment.
Do you have plans or interest in building a sheltered playground? Please fill out the form, and a specialist will contact you one-on-one! #ShelteredPlayground #SemiOutdoorSportsCourt #SolarEnergy #SolarPhotovoltaicSportsCourt #SolarShelteredCourt #SolarPanelSportsCourt #EnergySavingAndEnvironmentalProtection #HornSpeaker #ColumnSpeaker #PASystem #SoundReinforcementSystem #WaterproofColumnSpeaker
