The body of all of our work here at Hearlink, is based on noise and sounds. Our ethos is built on bringing the most dynamic sound portfolio possible, to those who cannot experience it naturally. To understand how to amplify noise and sound for our patients, we need to understand how it works.
We refer to sound as energy, and it travels in waves. We measure it in both frequency and in amplitude. Amplitude will show just how forceful that wave of sound can be. The unit of measure is a decibel, or dBA. 0 dBA is on the soft end of the spectrum, in fact, the softest level that a person can hear and understand. To put that in perspective, a normal level of conversation is around 65 dBA and a rock concert or a sporting event can be more than 120dBA. Any sound that measures over 85 dBA has the potential to cause permanent damage to your ears. The higher the level of sound pressure that a sound has, the less time it will take to cause any kind of damage to your ears. Let’s look at an example: A sound that is moving at 85 dBA will take up to eight hours to cause its permanent damage. A sound at 100 dBA will begin to start damaging the hair cells in your ears after a paltry 30 minutes of listening experience.
Frequency on the other hand, is always measured in sound vibrations, specifically- the number of sound vibrations, which take place in the span of a single second. These are measured in the metric, Hertz. If your ears are healthy, then you can hear sounds that range from very low frequency (20 cycles per second, or 20 Hertz) all the way to an extremely high frequency of 20,000 Hertz. If you’re a fan of piano music, the lowest A key is 27 Hetz. The middle C is 262 Hertz. The very highest key on the piano is a whopping 4186 Hertz.
There is a metric called the decibel meter, which will show different examples of things that create noise, and then measure these things in decibels. There is also an instrument called the sound level meter. The sound level meter measures sound level, most commonly in noise pollution studies. These are extremely helpful in the audiology field and study the quantification of the different types of noise out there, especially within environmental, aircraft and industrial environments. There is an important difference to note here. The readings from a sound level meter are not the same as human-understood loudness. Loudness that a human ear can comprehend is much better measured by something called a loudness meter. There is an international standard, which clearly specifies the functionality and the performance of a sound level meter. It is the IEC (International Electrotechnical Commission) 61672-1:2013.
Questions about how to measure sound or how that ties into the different products and solutions that we work with? Feel free to reach out to any of our team members with questions and comments that you might have.