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.
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.
Solent Acoustics has recently taken delivery of an impedance gun kit from Microflown, used for the in-situ measurement of sound absorption coefficient.
The kit contains the impedance gun itself, which is constructed of a loudspeaker and PU Probe (for the measurement of both pressure and particle velocity), and a Scout V2 USB data acquisition system. Software provided by Microflown allows for the calculation of acoustic absorption coefficient from the measurement of pressure and particle velocity, which also allows for measurement of acoustic intensity.