The sound level meter is the instrument used to measure the intensity of sounds, and it performs that measurement in decibels (dB SPL). Its most widespread use is to measure noise pollution, but for those of us with hyperacusis it can be an excellent tool to more accurately know the noise level to which we are being exposed, or as an indicator of when we should use hearing protection. It is even more useful for those who have developed phonophobia and are afraid even of sounds that cannot cause them any harm, since it provides us with an objective value of intensity that helps to calm the negative response to sound.
 |
| Sound level meter* |
People with hyperacusis have difficulty tolerating sound 24 hours a day, so it would be a major inconvenience to have to carry a sound level meter wherever we go. However, since smartphones have become inseparable companions and there are multiple free apps that turn our phone into a sound level meter, that problem is solved.
That said, the accuracy of those mobile apps cannot compare to that of a real sound level meter. In general, they are not suitable for measurements above 100 dB, they lack windshields, and their microphones are designed to capture the human voice. However, for our purposes we do not need an exact measurement; an approximate value is sufficient. In any case, once we have made a few measurements we will have enough information to compare the intensity of the sounds around us and get an idea of their potential danger, regardless of whether the measured value is perfectly accurate or not.
iPhone users can download sound level meter apps that make fairly accurate measurements. Among these options are Faber Acoustical or Decibel 10th.
For Android users, on the other hand, since there are many models from different manufacturers, the hardware also varies and therefore the sensitivity of the microphones is different. In this case it is necessary to calibrate the device. Not all the sound level meter apps available for Android allow calibration, so any app we download to function as a sound level meter must meet this requirement. Some examples of sound level meters for Android are Sonómetro by Abc Apps, Sonómetro by Smart Tools, or a more sophisticated one like Noise Meter.
How to calibrate a sound level meter on a smartphone
In the absence of an acoustic calibrator to make the adjustment as accurate as possible, I will mention a couple of simple methods to calibrate the sound level meter on our Android and obtain measurements that are at least reasonably close to reality.
In the Settings tab of the sound level meter you have installed on your phone you will find the calibration option, where you can enter a dB value that is added to or subtracted from the default microphone reading. The calibration should be carried out in a very quiet room.
 |
| Calibration settings of the Abc Apps sound level meter |
To calibrate it you can do the following:
-
Find the value that makes the sound level meter read about 32 dB in a quiet room.
-
Find the value that makes the app give readings between 50 and 60 dB when speaking at a distance of approximately 1 m from the phone (some peaks above 60 dB may appear). Of course, for this to work, one must speak at a normal volume. Anyone who speaks into their shirt collar or shouts like a shepherd in the middle of a field will have to make an effort to adopt a normal speaking volume if they want this calibration to be effective, or ask someone else to do it for them.
I have compared these settings with the readings from a real sound level meter and the results are similar.
No comments:
Post a Comment