If you've flown on a commercial airline since 2000, you've probably seen people wearing Bose QuietComfort headphones. They're expensive and large, and I don't like them.
Their noise-cancellation circuitry actually generates noise of its own, and my ears are good enough to hear it as long as I'm not seated too near the engines.
I started wearing earplugs on airplanes in the 1980s when I discovered the squishy memory-foam type. They block noise better than headphones ever could, and they don't make any noise themselves.
But when I bought my first iPod, that strategy didn't seem quite so perfect anymore. The ear-bud headphones that came with the iPod never fit me at all; they just fell out. After some experimentation with small folding travel headphones, I decided I was happiest with in-ear headphones. They gave me most of the noise reduction of the foam earplugs along with the ability to listen to music.
The problem with in-ear headphones is finding a model that fits me. I gather that this is a common problem with this type of product. I went through several low- and mid-priced models before settling on the old Apple In-Ear headphones--they just worked the best for me. (Interestingly, I had the same experience as CNET's Steve Guttenberg when he reviewed them: they only fit well when inserted upside-down.)
But my big problem with the Apple In-Ear headphones was that they're fragile, at least when inserted upside-down like that, a usage that Apple may not have designed them to handle. I managed to break my first set after about six months of occasional use. One of the strain reliefs, made of soft silicone rubber, split in two at the body of the earphone, and the wire broke inside shortly thereafter.
At this point I thought about buying a really nice pair of in-ear headphones, like something from Etymotic Research, but I couldn't bring myself to spend a lot of money on headphones I only wear on airplanes.
I eventually bought another set of the same Apple headphones and was more careful with them. They lasted a couple of years before one of the strain reliefs split, and survived another year of gingerly handling before the wiring connection became unreliable earlier this year.
I was going to get a third set--at under $40, they were a good deal--but it turns out that Apple discontinued these headphones and now offers a new model with iPhone support (remote-control buttons and a microphone on the cord) for $79, about twice the price. That was enough to make me hold off on the purchase.
So when I received a press release in July from the Klipsch Group announcing the iPhone-compatible Klipsch Image S4i In-Ear Headset, I wrote to request a sample. Klipsch sent them right out, and they arrived the day before I left for Siggraph.
I had connecting flights to New Orleans with long layovers in both directions, so I had plenty of time to test these headphones. I was even able to make some direct comparisons with the Apple headphones by fiddling with the broken wire while holding my head still.
My immediate impression was that with the default ear tips, the Klipsch headphones were about as comfortable as the Apple headphones and provided better sound isolation because they could be inserted deeper into the ear canal.
But they were also slightly more sensitive to their precise position in my ear; slight misalignments (like those caused by tension on the cords) "broke the seal," allowing a little more noise to sneak past. This probably wouldn't bother me much except that it's quite noticeable when one ear is fitting well and the other isn't.
I found that rotating the unique oval ear tips could improve the fit and make it less sensitive to unintentional tugs on the cords, but even after days of experimentation I never really found a complete solution. I also eventually stopped trying for maximum sound isolation; shallower insertion provided better long-term comfort. Klipsch provides three additional sets of ear tips, but none fit me as well as the standard "medium" size, so that didn't help me. Your mileage may vary, as they say.
Nevertheless, the S4i headphones work very well when they're properly positioned. They're more efficient than the Apple headphones, producing more volume for the same volume setting, and the bass response is a huge improvement. In fact, adjusted for the same overall volume level, the Klipsch headphones produce slightly stronger bass than my full-size Sennheiser HD 595 headphones. I'm tempted to assume the Sennheisers are being more faithful to the original sound, but lacking any way to measure frequency response curves, I can't say for sure.
In fact, even in a quiet room, the Klipsch sound quality overall is surprisingly close to that of the Sennheisers, which I really didn't expect considering their relatively tiny size and much lower price. There are still significant differences, but I'm pretty sure I'd never notice them in flight. I suppose the intense competition in this market segment has driven a lot of technical progress, which as usual turns out to be good for everyone.
The S4i also works well as a phone headset, though I probably won't be using it that way very much since I have (and love) the Aliph Jawbone 2 (which I see has now been obsoleted by a newer model). I made a couple of test calls, and clarity was good in both directions. Klipsch advised me, and I can confirm, that the S4i's volume controls don't work on the original iPhone or iPhone 3G, but they do work on the iPhone 3GS. This isn't a problem with the headphones; Apple's headset has the same issue.
Bottom line, I'm very impressed by the Image S4i. They're more expensive than Apple's product, but $79 cheaper than Etymotic's competing hf2 headset.
I wish it were possible to test-fit in-ear headphones in stores, but for hygienic reasons that isn't really practical. Aside from the sometimes inconsistent fit, however, I can recommend the Image S4i as a great combination of comfort, functionality, and sound quality.
And I'll still never wear big clunky headphones on airplanes unless the headphones are made by David Clark and I'm sitting in the cockpit.