Headphone culture in Japan
For fellow headphone/earphone enthusiasts, Japanese makers are known for superbly built gears uniquely differentiating them from their European and American counterparts. Here, earphone and headphone is a common commodity and you can see people using them almost anywhere (based on personal observation) in Tokyo.
For most Japanese, the easiest way to acquire a piece of headphone can be done at department stores such as BicCamera, LABI, or Yodobashi, conveniently located at strategic location close to major train station. These stores usually provide price lower than recommended retail price set by the maker, and if you're a visitor from abroad you can be waived off the consumer's tax (5%) if you show your passport during payment.
Yodobashi-Akiba located at Akihabara, Tokyo.
The best thing about these stores would be almost all headphones/earphones can be auditioned, including those high end models priced astronomically (such as Final Audio Design's Piano Forte or headphones made of exotic materials) that usually is locked in glass display. All you need to do is just wave down one of the staff and indicate you're interested to try it out.
Of course, this is also the land of limited edition gears, like the most recent Audio Technica's 50th Anniversary headphones/earphones. Some other noticeable example would be Shure SE535 Asia Special Edition which is coated in red and said to sounded different compared to the stock SE535.
It takes time to go through the headphones but ultimately you'll be pleased as you have the leisure of trying them out before deciding which is your final choice.
In case you plan to travel to Japan to hunt for headphones, remember to charge up your listening gears before auditioning those headphones!
Just the tip of the iceberg, of all the headphones/earphones you can try over here.
Certain stores have special corner equipped with CD player and amplifier that allows people to audition with their own CDs. Usually the audition headphones are higher end models like wooden ones.
My personal favourite spot would be BicCamera located at Shinjuku station's west entrance (ビックカメラ新宿西口店) at Tokyo, for it's mass collection of headphones, well-maintained and relatively quieter compared to other stores. Other spots I would recommend is Yodobashi Akiba or BicCamera's newest outlet at Shinjuku station's east gate.
If shopping with the mass isn't your cup of tea, it is still possible to purchase them online.
Kakaku.com (Japanese) is a well-known online shopping site where you can compare the price of a specific item and hunt down the cheapest price in town.
Amazon Japan would be more familiar for the international audience. Although they do provide international delivery, unfortunately headphone/earphone is only limited to domestic delivery. However, I've heard of service such that the goods will be delivered to a Japanese address and then they'll help ship the goods to your address out of Japan, acting as the middle man.
Second hand shops is also a good treasure-hunting site if you don't mind used item or if you're short of cash but eager to own a piece of the headgear. Most Japanese kept their stuffs well and even if it's used, it's still in good condition. So far I've visited Fujiya Avic located at Nakano, Tokyo but of course, there are a lot more treasure hunting second hand goods shops out there.
Do keep in mind that American brands (Shure, Westone, Ultimate Ears etc) are being sold more than they cost in the US, and same goes to European cans (Sennheiser, AKG). So if you're looking for non-Japanese headphone, perhaps you should check out your backyard again.