Headphones
Choosing your next headphones.
Here’s a quick guide to the different types of headphones, along with the benefits and drawbacks of each.
Specs vs sound quality - which matters more when choosing your headphones?
One should generally ignore the manufacturers’ specifications when choosing headphones, especially frequency-response numbers as there is no standard testing methodology for headphone frequency response and many vendors tend to exaggerate the specs for marketing purposes. Given that the specs published are accurate, these numbers do not actually tell you how that particular set of headphones actually sounds.
Instead of relying on the specs, it would be best to rely on your own ears. Or, if you can’t test out the headphones personally, read reviews from a trusted source who has tested it out.
As with speakers, a quality set of headphones reproduces audio with good balance between the treble (upper), midrange, and bass (lower) frequencies, producing full, rich sound while preserving detail.
Note however that because headphones use small drivers (speakers), bass response would naturally be inferior to that of huge speaker woofers where you can not only hear but also feel the drivers. Most headphones are unable to reproduce the visceral impact of low bass – you can hear it but you can’t feel it.
As such, many vendors would attempt to address this issue by emphasizing certain bass and upper-bass frequencies to give their headphones that extra boost in hope that their headphones would stand out from others. This boost would be great for people who use their headphones for exercising and other physical activities however, these type of headphones become strenuous to listen to over time. If your listening interest lies in the accurate audio reproduction, be reminded not to be blown away or swayed by the emphasised bass (or exaggerated treble detail).
The best approach would be to test a set of headphones for several hours (or several days if you can) and with varied types of music. If you feel that the set of headphones sounds great with most types of music, then chances are this set would fulfil your requirements in the long run. However, as it is not always possible to test a set of headphones for several days, or hours even, your best bet would be to rely on a reliable source, noting however that the tester may not have the same preferences as yourself.
In-Ear Canal Headphones 
Also known as canalphones, these use eartips that fit snugly and fairly deep in your ear canals. They block external noise, so they're great for travel and noisy environments, and the better models sound great. However, some people find canal phones to be uncomfortable, and the best ones are very expensive.
Pros : Portable, compact, great noise isolation and sound
Cons : Uncomfortable for some, blocks the surrounding environment
Earbuds
Earbuds sit loosely in your outer ears. They do not produce outstanding sound, but they are compact and relatively inexpensive.
Pros : Portable, compact, inexpensive
Cons : Mediocre sound, no isolation, often cheap quality
Canalbuds
A middle ground between earbuds and in-ear-canal models, canalbuds generally use smaller eartips than the latter and sit just inside the ends of your ear canals. They tend to be more comfortable than true canalphones; they're also usually less expensive. Sound quality is generally in between that of earbuds and canalphones.
Pros : Portable, compact, comfortable, good sound quality
Cons : Mediocre noise isolation, sound quality not as good as that of true canalphones
Lightweight Headphones
These use larger drivers than earbuds, canalphones, and canalbuds, and their similarly larger earpieces rest against the outside of the ears. Most have a thin headband that goes over or behind the head; some use a small clip on each earpiece that slips over the ear. Some also fold up for easier traveling. The best produce impressive sound quality.
Pros : Portable, comfortable, good bass response
Cons : Not as compact as earbuds and in-ear-canal models
Full size Headphones
These fully cover or surround your ears, and good ones sound better than good lightweight models. Many are also very comfortable thanks to generous padding and ergonomic designs. Closed full-size headphones block some degree of external noise (and also keep your music from disturbing others) while open models often sound better but let more noise in and out. One caveat: Some full- size headphones require more juice than a computer or portable device's headphone jack can provide- for power hungry cans. you'll want a dedicated headphone amplifier to get the best sound quality
Pros : Comfortable. great sound quality (with enough power), solid bass response
Cons : Big and bulky, closed designs sometimes come with audio tradeoffs, open designs provide little noise isolation and often leak sound
Noise-cancelling Headphones
Noise-cancelling headphones are not to be confused with noise-isolating headphones. Concisely, noise isolating headphones physically block ambient noise with their seal against your ear whereas noise cancelling may do that too but also cancel the actual sound waves electronically. Noise-cancelling headphones use active (battery-powered) circuitry in addition to passive noise isolation. These models sample outside sound and then pipe in an inverse audio signal to "cancel out” - or at least reduce - a good amount of monotonous noise, making them great for travel or use in a noisy office. Although they don't usually sound as good as comparably priced in-ear canal headphones, noise-cancelling models are easier to put on and take off, and they let you hear what's going on around you. Full-size models provide the best isolation and audio quality
Pros : Comfortable, good noise isolation and reduction
Cons : Can be big and bulky. rarely great audio quality, noise-cancellation circuity can be audible, some models require batteries even for use as standard headphones.
Bluetooth Stereo Headphones
Using stereo Bluetooth (A2DP) technology, these models let you stream audio from recent computers, smartphones, and tablets. Most also double as headsets, letting you switch between music and voice features (for phone calls, for example), and most provide music-playback and volume-control buttons.
Pros : Portable, wireless, comfortable, some are great for exercise
Cons : Possible wireless interference, often mediocre sound quality