Earphones are by far the easiest and most cost-effective way to listen to music. Earphones offer not only the conveniences of portability and durability, but also tend to represent a higher value for money, in terms of absolute sound quality with regards to sound resolution and expression of detail, than full-sized headphones. They lack the more refined aspects of sound presentation that can only be reproduced by proper speakers or open headphones, like a sense of 3-dimensional space, but some high-end multi-driver earphones can simulate these aspects very effectively. They also function as multi-purpose listening devices, as they can be used with cell phones to increase call quality and isolation from unwanted noise; some even feature microphones and volume and/or track controls to this end. Some people even use earphones at concerts to help protect their hearing.
The earphones in these lists have been chosen as the best for their particular price points and target audience, offering different solutions for casual listeners, audiophiles, studio engineers, and performing musicians, and ranging in price from pocket change to serious investment. The best way to shop for an earphone is to try as many of them as possible; if that is not an option, it's generally wise to set a price limit, and pick the best earbuds in 2021 for your listening style and preferred genres. Also keep in mind that, while sound is usually the most important feature, how much you enjoy the earphone is also going to depend on how happy you are with the amount of money you spend; if you pick an earphone from these lists, and feel that you've been ripped off, odds are you are either spending more than you personally wanted to spend on earphones, or your pick is missing some feature or characteristic that you were expecting, but perhaps didn't take into consideration.
There are two different types of driver technology used in modern earphones: dynamic drivers and balanced armatures. Most earphones, and indeed most headphones and speakers, use a dynamic driver, a moving diaphragm that vibrates in its entirety in order to produce different frequencies. They tend to be the most effective at producing pounding low frequencies, and higher-end dynamics give bass a tactile presence and texture that very few balanced armatures can match. Most of the earphones discussed here use dynamic drivers, unless otherwise noted.
Balanced armatures are a more complex type of speaker, having only very small moving parts, most widely known for their use in hearing aids, cochlear implants and other aural-assistive technologies, applications for which their small size makes them ideal. However, as armature technology has evolved, the quality of sound they can reproduce has increased drastically, and they are now featured in the majority of high-end earphones due to their tonal accuracy and decreased distortion. Balanced armature drivers tend to perform best in the mid and high frequencies, generally producing cleaner, more well-defined notes than dynamic drivers.
Newer, more expensive earphones tend to feature balanced armature drivers, and sometimes quite a few of them; our pick for Best High-End Earphone, the Shure SE846, utilizes four balanced armature drivers per side. Some modern earphones, like the K3003i, feature a hybrid design, using a dynamic driver to handle the bass frequencies and incorporating balanced armatures for mid and high frequencies.
These earphones have been hand-picked as the best value for money and overall performance; I feel confident that anyone following the buying guidelines above and taking time to carefully consider their choice will be very satisfied with their purchase.