6 Sep 2016
Noise. It is all NOISE!
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By Simon Byrne
Australia has no national framework for noise control, and national regulations and guidelines cover only a few aspects of the noise environment.
When I set out to write this, my goal was to deliver a comprehensive state by state guide of the local noise regulations and how they applied to our industry. It quickly became apparent that this was going to be tough.
This is because each state and territory has their own approach to managing noise regulations.
Some are comprehensive, well thought through, regulated properly, use proper physics and try to strike a balance between the needs for a thriving live music scene with those of their neighbours. Victoria gets a gold star for this which may in part explain why there is a strong live culture in that state.
Most are really vague and I’d argue, unworkable. For example in News South Wales, there is a concept of “offensive noise” within the regulations. Offensive noise is defined as “interferes unreasonably with (or is likely to interfere unreasonably with) the comfort or repose of a person who is outside the premises from which it is emitted.” That’s it! No reference levels, no measurements, no times at which the definition applies and it is certainly not a standard which you can measure and then take corrective action. This obviously leaves massive room for interpretation as what is offensive is highly debatable.
Noise usually falls under the State/Territory Government Environment portfolios, and regulations are introduced at a state level, which are then typically enforced by the local councils and the Police. In addition to those 3 layers, all State and Territories’ Liquor Licensing bodies usually impose noise restrictions on licensed premises.
If there is a common thread, it is that entertainment sound originating from a licensed premises, should not be heard inside a neighbour’s residence (even with the windows open). If a complaint is made to a liquor licensing board, it will probably get up and the licensee will need to take steps to fix the problem. The liquor license restrictions are on top of any other State noise regulation and are usually the most restrictive, and are on a case by case basis.
The forward looking jurisdictions are developing Entertainment Precincts/Hubs that recognise these activities create noise, yet need to be nurtured.
These State governments recognise that entertainment is an important contributor to the fabric of society and the economy. For example, Brisbane’s Fortitude Valley is an important entertainment hub for the city where there has been conflict between residents and the entertainment industry. To address these issues, Brisbane City Council has created a special entertainment precinct where the onus has been put on new developments to ensure noise management and attenuation measures are in place so that residents can coexist with the entertainment activities. Also, greater communication is being developed for potential residents. That is, making sure they understand that these areas are noisier than normal and that they should embrace that, or not move in! They have even developed the “Valley Sound Machine” which is an online tool that lets potential residents experience simulated noise levels at different times and places in the Fortitude Valley Special Entertainment Precinct.
Victoria is a leader in this too. Indeed, as of 2014, anyone selling a property in the Melbourne metropolitan area must provide a due diligence checklist to all potential buyers of residential properties which includes a notice about the increased noise that should be expected in urban areas such as the inner city. Once again, know what you are in for and if you don’t like it, don’t move in!
ACT and Tasmania are reviewing their regulations right now and appear to recognise that entertainment needs to be incorporated into their plans for a future vibrant society. NSW unfortunately don’t seem to be doing the same.
Until all jurisdictions recognise that entertainment is a crucial to a healthy and vibrant society, we will unfortunately continue to face challenges.
You’ll have noticed that I have not made a single reference to decibel levels, weightings, peak levels, spectral content or long term averages. That is because they don’t matter to the person who is complaining. If they hear noise and it is irritating them, they will complain.
What about Sound Level Meters?
The problem with sound level meters is that they reduce a highly complex waveform with an infinite number of variables to a single number.
Think about it in the visual domain. Say you take a photo of a scene of a golden sunset, on the beach, facing east, with some waves, with some surfers in the water, some people walking their dogs and some kids building a sandcastle. Now assign a single number to describe that entire scene.
It is the similar problem with sound. You are assigning a single number for a complex waveform ranging from 20Hz to 20,000hz. In frequency range, that is a 1,000 to 1 ratio and the amplitude varies by 1,000,000 to 1.
Despite this, they can be of real value to an audio operator because it provides a guide:
- The human hearing system is very good at hearing variations in relative level but not absolute levels. That means we are not good at consistently mixing at the same level every night.
- Depending on how loud last night’s show was, your hearing might still be recovering. Which in turn means you might be inclined to mix louder tonight without realising it. A meter helps you deliver consistent levels. As a side note, If I am a punter at a concert, I’ll often use ear plugs if I know that I am mixing the next day.
- If you are operating under noise level restrictions, you have a reference to work to.
You must accept though, that unless you have professional training in sound level measurement, and your equipment is calibrated that your readings really are just a guide.
What to look for in a sound level meter
At a minimum:
- A, C and Z (unweighted) readings.
- Slow and Fast response.
- The ability to be calibrated
- Type 2 – This refers to the IEC 61672 Standard and the tolerances contained in the standard. Type 1 is really good, very tight tolerances, expensive and used for laboratory and legal type work. Type 2 is a looser but still accurate (+/- 2db), more cost effective standard.
Where sound measurement standards exist within regulation, they tend to be A Weighted, Fast Response.
Nice to have:
Leq – Leq is the preferred method to describe sound levels that vary over time, resulting in a single decibel value which takes into account the total sound energy over the period of time of interest.
This is a useful guide to how much sound you are exposing the audience over the period of your event.
Unfortunately for Android and Windows phone users, probably not. The hardware manufacturers of these phones design them in isolation, to varying costs, specify and source their parts from lot’s of different suppliers. It is challenging for an App developer to account for these variables so they tend to be inconsistent.
iPhones however can be ok (+/- 2db, Type 2) provided they are calibrated correctly and especially with an external microphone.
iPhones are a closed ecosystem so App developers have been able to confidently develop their apps with known hardware and software.
They aren’t without their problems though:
- Stability – Studies have shown that iPhones calibration shift as they age. This makes sense when think of how how roughly we treat our phones.
- Phone cases – A phone case can dramatically interfere with readings.
- Calibration – They need to be calibrated and verified in order to be confident of the data you are seeing.
Brisbane Council’s Music Harmony Plan (Fortitude Valley Music Precinct):
Study on Smartphones as Sound Level Meters
SPLnFFT Noise Meter App for iPhone
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