Earplugs for Commuters

Recently I have moved down to London for a placement role as an acoustic consultant over the next year (before I go back to uni and finish my degree). Since being here I have learnt many new things about my subject as well as been getting into the London life and that as a commuter in a working job. Because of this I have obviously been spending a fair amount of time on tubes and trains around the capital, and have been getting to know the tube map quite well. Anyway, it was as I was on one of these tube journeys the other day that I had a thought – should commuters wear ear plugs?

London Underground

It was as I was on the Jubilee line that I noticed high noise levels, so being the acoustician I am, I pulled out my iPhone and opened up the dB meter app. As I looked at the screen I was shocked to see levels around 90-100dB. If you are not aware of the scale of deciBels, this is about the same level as a klaxon or a nightclub. For workers, there are regulations set out to employers for daily/weekly exposures that employees can experience. These are 80dB as a lower limit and 85dB as an upper limit, whereby hearing protection should be provided for the lower limit and hearing protection is mandatory at the upper limit. Note, these aren’t maximum levels that can be experienced, but average levels over a whole working  day/week. Although saying this, if a commuter had an hour commute each day (to and from work) with an average level of 86dB during these periods, then they would have already reached the lower action limit of their daily noise dose! For occasional exceedances, there is a level of acceptability in this, however for continued exceedance, long term effects can occur.

The image below shows a noise map for Zones 1-3 on the tube produced by London Southbank University. These levels are averages, so theoretically higher levels are possible that what is shown.

Noise map of zones 1-3 of London underground, produced by London Soutbank University

Noise map of zones 1-3 of London underground, produced by London Soutbank University

With newer trains being introduced to the underground, these levels are being reduced to a more acceptable level (see the circle line above) however should we do something about it ourselves?

One option is for commuters to wear earplugs, however I don’t realistically see any chance that TfL may start handing out free earplugs or commuters wearing them any time soon! The alternative I see is simple and is already common to many commuters already – headphones. With headphones in our ears, even though we are adding extra noise, we are also reducing the background noise around us, thus reducing noise exposure (so long as we don’t have our music too loud – but that’s an issue for another day)!

From what I found by looking at various sources, I reckon that a standard set of headphones can reduce ambient noise by 20-30dB (depending on quality/type) with noise-cancelling headphones giving even more attenuation. Due to an acoustic phenomenon called sound masking, we can assume that anything that is more than 10dB less than the dominant level is not clearly audible, thus making the background noise from our commute seem no problem compared to our music. There will still be elements that we do notice however, mainly bassy rumbles and thuds, but this is because headphones do not produce low frequencies like this so well.

With the world around us getting noisier than ever, we need to protect our hearing as otherwise we will lose it later on in life. A daily commute is something that so many don’t even think to be a problem, when really it can be, but we’ve just learnt to live with it. What is your daily commute like, do you ever worry about it being to loud?

Notes

[1] London Southbank University Research

[2] Sennheiser Website

[3] Health and Safety Executive Wesite – http://www.hse.gov.uk/noise/index.htm

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Beats by Apple

So those who know me will know that I like my tech, especially that which has a shiny apple on the back of it, which meant I was interested to read this week about Apple’s latest purchase. If you hadn’t already heard, Apple are currently in the process of buying Beats, the headphone brand that Dr Dre is co-founder of for $3.2bn. Generally speaking, this didn’t really surprise me, but deep down I kind of wish it had shocked me more… Let me explain.

Beats

Beats are a brand that can really split opinion (like Apple) and this opinion massively depends on who you ask. Ask most people on the morning commute and I imagine that most of them will like, or possibly own Beats, but ask any audio geek or tech fan and 9 times out of 10 they will probably have the opposite opinion. The brand is one that is very desirable and aesthetic based which, although is not a bad thing, can mean that you pay extra for the letter ‘b’ on each ear ‘can’. If this is compared to a brand like Bose for example, whose business strap line is ‘Better sound through research’, vast differences can easily be seen.

Bose (or Sennheiser for example) are both tech companies, based to create products with cutting edge tech that sounds great, whereas Beats do that with more of an emphasis on image (this is starting to remind me about the whole Apple vs Microsoft debate!). Headphones naturally are a more desirable accessory to own (as written about by a blog from Trevor Cox when comparing public perceptions for headphones vs loudspeakers), so I guess part of this comparison between companies could be to do with the background of the company.

Infograph of most common words associated with Headphones and Loudspeakers. Words nearer top related more to loudspeakers and vice versa. Words on right more commonly used than those on left. Credit Prof Trevor Cox

Infograph of most common words associated with Headphones and Loudspeakers. Words nearer top related more to loudspeakers and vice versa. Words on right more commonly used than those on left. Credit Prof Trevor Cox

One major conflict of agreement will come when the quality of audio produced by Beats headphones is mentioned, some love it, some say it is awful. For me, I would prefer a pair of headphones by a tech company, but I can see that Beats do make some good sound. The main advantage to Beats audio quality is that there is bass and lots of it. The target market for these is primarily younger who listen to bassier music, which makes sense. Bass tones have the effect of making the user feel like that the sound is more immersive. This is to do with the wavelengths of bass sounds being bigger, hence it physically surrounding the listener more meaning they can feel the sound, not only through their ears. However, bass is not the be all and end all of audio quality; there are many more things to look out for in a good set of headphones (Comfort, Clarity, Sound Isolation, Frequency range, Price/Value for money…).

So if the quality is not so good, why do people buy them? To be honest, most people may not be able to notice the difference, or may not really care. One of my course mates wrote an interesting blog this week on whether we really care about the quality of our music, or whether we just go for convenience which I would recommend if you get a chance. One other main factor is again about appearance, if you’re going to spend £100-200 on some headphones, you want them to be noticed!

To me, Apple is a company of quality, yes with a big emphasis on image, but mainly focused on quality (more generally speaking and not when it came to audio!). Hence, when I saw they were buying Beats, I was kind of disappointed that they had opted for image over top end quality. Saying this though I can’t imagine them ever having bought a company like Bose or Sennheiser. When it come to brands (particularly those that make tech) people really buy into products, which is a factor that makes a huge difference (e.g. opinions of peers etc). Because of this I can imagine plenty of you will have different opinions to me! I would love to hear these if you want to comment below, alternatively click below which of the two options you’d choose!

Notes

[1] BBC News article – http://www.bbc.co.uk/news/blogs-magazine-monitor-27340356