When my iPod’s basic headphones died, I bought the wooden JVC Victor HP-FX500 model earphones for about JPY 15,000. These have a wooden trembler, and so the sound is very natural.
If you like to listen to anything acoustic, jazz, classical, opera and so forth, these are great ‘phones. They have 100dB/1mW sensitivity and 8Hz to 25kHz frequency response. If you have never used an in-ear ‘phone before, they take a bit of getting used to, as they shut out pretty much all other sound. It’s a little disconcerting to be able to hear your own heartbeat, but they sound wonderful.