There are a number of methods of simulating ultrasonic guided wave propagation in COMSOL (v6.1) which I will discuss in
Sonic booms are something that most people will have heard at some point in their lives, perhaps from planes passing by at an airshow, or from a bull whip (yes, the tip travels faster than the speed of sound!), but what exactly are they? and how do they produce such an incredible noise? This posts explores the acoustics of sonic booms.
The modern sound level meter is a powerful tool with many useful functions, but what are the most important things to know? This post aims to act as a simple to follow guide.
Written by Lee Davison
As acousticians, we know (or like to think!) that the sound around us affects us in ways that most people don’t realise. Whether it’s reverb in your classroom that means you can’t hear the teacher properly, or in the shower making you think you’re a great singer, the acoustic spaces around us have a pretty profound effect on the way we experience life, that often goes unnoticed.
This makes you wonder what the ideal acoustic specification for a space is. What’s the best reverb time for music, or the best noise level for concentrating, or perhaps being creative? This is the question that Ravi Mehta, Rui Zhu and Amar Cheema undertook to answer in their 2012 paper; “Is Noise Always Bad? Exploring the Effects of Ambient Noise on Creative Cognition”.1
Have you ever covered your ears with your hands to protect yourself from loud noise? That’s the closest to natural hearing protection that we’ve got, but just how much does it reduce the sound pressure level reaching your ear? And what’s the best method? This experiment aims to find out.
In our previous reverberation time measurement tutorial an impulse response, created by bursting a balloon, was used as the measurement signal. This is a quick and simple method of carrying out a reverberation time measurement, but may not be the most accurate method. In this tutorial we will look at an alternative method that can provide improved results.
The World Health Organisation states that loud noise is the single biggest preventable cause of hearing loss in the UK. Due to advances in portable media player technology, users are now able to store and play music for much longer. Due to this, there is a huge potential risk for overexposure to noise using these devices. It is now estimated that over 4 million young people in the UK are suffering with the effects of noise induced hearing loss from listening to amplified music in the UK.
Around 10% of all adults in the UK suffer from tinnitus, with some reporting depression, sleep deprivation, and anxiety, which are having a considerable negative impact on their quality of life. There is currently no direct cure for tinnitus, most treatments are for other medical conditions that may be causing tinnitus as a side effect, or using relaxation techniques and noise masking to block its effects temporarily. Although for many patients tinnitus can dull over time, for some the condition only gets worse with age.
It may be common knowledge that cupping your hand around your ear can help to amplify sounds, making speech more intelligible or making a distant whisper just a little louder, but what does the hand do to the ear to make it easier to hear these sounds?
To better understand the difficulties of living with various types of hearing loss we have created this simple comparison using a piece of music and an audiobook, that explores the differences between broadband hearing loss, notches (or noise induced hearing loss), old age, and tinnitus.