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My patience with the noise of airlines has run out, on my trip from AU to US I didn’t get any sleep due to the cramped seat and the noise of the plane. While I can’t do anything about the cramped seat without spending a lot of money it seems that I can do something about the noise with moderate expense.
I’ve been researching Noise Canceling Headphones . The principle of such devices is that they have a microphone on the outside and a speaker on the inside to generate sound that is 180 degrees out of phase which will then almost cancel out the ambient noise. Apparently such devices are very effective for low frequencies but less effective for high frequencies. High frequencies are more easily blocked by sound insulation, so the ideal seems to be “around the ear” headphones with lots of padding to passively stop noise with active noise canceling to deal with the lower frequencies.
So I’m now planning on buying a set of headphones before I leave the US.
Choice Magazine (an Australian independent product review organisation) published a review of noise canceling headphones in 2007, it has some interesting information but is not suitable for buying advice today . Choice gave the best results to the Jabra C820s which had just gone out of production when they published the review and by now could only be bought on eBay. The Jabra had an active cancellation of 14.3dB and a passive cancellation of 8.3dB. The best active cancellation of all the reviewed products was 19.5dB for the Bose QuietComfort 3 – which incidentally only had a passive cancellation of 4.8dB. Both the Bose and Jabra products got good reviews in a mailing list discussion. It’s a pity that Jabra is now only manufacturing products for call centers.
I am not considering the headphones that go on top of the ears, they will inherently give less passive protection due to the design and they will annoy me. I am also not considering the ear-buds because I don’t like putting things in my ears. I will note that there are some very positive reviews of some of the ear-bud devices. The Etymotic Research devices get very good reviews and are apparently on sale at reasonable prices in Apple stores (among other places) . Anyone who wants noise-canceling headphones and disagrees with me about the desirability of ear-bud type devices should probably consider them.
The Bose QuietComfort 15 is selling for $300 (NB for this post all prices will be in US dollars) . It has microphones both inside and outside the ear cup to allow better detection of ambient sound. A single AAA battery is supposed to last 35 hours, it has a detachable audio cable (for use in just blocking noise), and comes with an airline adapter (for the two-port airline sockets). It does require being turned on to listen to audio, some headphones allow you to turn off the noise canceling feature to listen to music without a battery – this doesn’t matter for my planned use. They have a volume switch (low and high settings) to cope with airlines that set the volume too high. They are specifically designed for passengers in commercial jet aircraft. Surprisingly the Bose web site doesn’t mention the number of dB of audio protection and none of the reviews I have read have mentioned it either.
The store Brookstone was recommended, they have some unbranded noise canceling headphones, but as they are on the ear and more expensive than comparable Sony products ($130 vs $100) I eliminated them quickly.
Sony has a good range of noise-canceling headphones . They have ear-buds starting at $90 and on-ear headphones for as little as $50. They have two models of over the ear headphones that are advertised at $200 and $400. The MDR-NC60 costs $200 and reduces noise by 12dB at 200Hz while the MDR-NC500D costs $400 and reduces noise by 20dB at 160Hz. I don’t know why they didn’t measure both headphones at the same frequency or give any information on passive sound insulation. They state that the MDR-NC500D was voted as being better than the Bose QC2 and QC3 but made no such claim about the MDR-NC60 – presumably the older Bose devices were rated as better than the MDR-NC60, and I have to wonder about how the Bose QC15 would compare to the MDR-NC500D. The MDR-NC500D has an internal Lithium-Ion battery that lasts 16 hours and can take a pair of AA batteries as well for a total of 28 hours.
The Sennheiser PXC 350 claims up to 32dB of passive attenuation and up to 18dB of active noise compensation . Their claims about NoiseGuard (TM) cause me to lack confidence in their products. The PXC 350 is advertised at $330 and the reviews that I have read suggest that the Bose might be a better product. Sennheiser also has PXC 450 which offers 23dB of active noise compensation and costs $450. I am not going to pay $450 for headphones.
It seems that the choice for over the ear noise canceling headphones comes down to the Sony MDR-NC60 at $200 and the Bose QuietComfort 15 at $300. I have the impression that the Bose product is better, but whether it is $100 better is the question. Also while I haven’t forgiven Sony for Rootkitting their customers , this is not going to prevent me from buying the headphones that best suit my needs.
Does anyone have any suggestions? Did I miss a good brand that I should be considering? Does Sennheiser have some redeeming features that I missed?