Earphones are very small headphones that are fitted directly in the outer ear, facing but not inserted in the ear canal. Earphones are portable and convenient, but many people consider them uncomfortable.[16] They provide hardly any acoustic isolation and leave room for ambient noise to seep in; users may turn up the volume dangerously high to compensate, at the risk of causing hearing loss.[16][17] On the other hand, they let the user be better aware of their surroundings. Since the early days of the transistor radio, earphones have commonly been bundled with personal music devices. They are sold at times with foam pads for comfort. (The use of the term earbuds, which has been around since at least 1984, did not hit its peak until after 2001, with the success of Apple's MP3 player.[18])
For older models of telephones, the headset microphone impedance is different from that of the original handset, requiring a telephone amplifier for the telephone headset. A telephone amplifier provides basic pin-alignment similar to a telephone headset adaptor, but it also offers sound amplification for the microphone as well as the loudspeakers. Most models of telephone amplifiers offer volume control for loudspeaker as well as microphone, mute function and switching between headset and handset. Telephone amplifiers are powered by batteries or AC adaptors.
Just a few hours of burn-in today – I don’t expect much change with Tesla-quality drivers etc. The treble is recessed almost as much as the Philips M1 I had, kind-of a worst-case scenario. So I took out my most minimal non-peaky non-bright non-sibilant headphone – the B&O H6, and even though it doesn’t sound the same as the T51p because of the H6’s “light” midrange, I wanted to get a sense of how much the T51p was recessed below a very minimal treble. My Foobar2000 settings were +2 at 2.5, +4 at 3.5, +2 at 5, +4 at 7, +6 at 10, 14, and 20 khz. Normally I wouldn’t do the dip at 5 khz, but the T51p has a nasty 10 db peak around 5 khz, which makes it difficult for portable use without a customizable equalizer. Without a treble boost it sounds very boomy as well as muffled. I can understand Beyer going to a darker sound with more bass – in fact I thought it was a move in the right direction. But they need to cut that (resonant?) peak around 5 khz. I compared to several other headphones and none of those were anything like that.
Noise cancellation: Noise-cancelling headphones play specific tones, much like white noise, to cancel out all of the sound around you and allow you to enjoy your music uninterrupted. Noise-cancellation is an active process, so headphones with this feature require batteries. If you’re a frequent flyer, or if you’ve got a noisy commute to work each day, you’ll love noise-cancelling headphones: they’re fantastic at keeping the cacophony of the outside world at bay.
The Bose QuietComfort 25 were released in 2015 and you can still buy them today. They are kind of like a wired version of the Bose QuietComfort 35. They have a slightly dated look, and boast almost as good levels of active noise-cancellation and sound quality as Bose’s QuietComfort 35. The important thing to remember is that even though these are wired headphones, they still need to be charged so you can turn on the active noise cancellation. Otherwise, they just work as normal over-ear headphones.
One thing I suggest to prospective customers for a specific headphone, if I have that headphone on hand, is for them to suggest 2 or 3 music tracks by a particular artist and composer that I can sample on that headphone, not so much for me to suggest how it sounds, but mostly to check if that headphone has any real sonic issues with that music. For example, a headphone that’s ideal for classical and acoustic music might sound too harsh with metal and industrial goth.
The WH-1000xM3’s advanced control systems allow you to let in various levels of ambient sound, with advanced features like voice-only mode, which helps filter through vocal frequencies so you can hear your music and the voices around you while blocking out other sounds. Responsive touch controls let you navigate volume, make calls, and play and pause music with ease, all while helping to maintain a clean aesthetic. Best of all, the WH-1000xM3 offer a staggering 30 hours of battery life, providing even heavy users with days of use from a single charge, and have a quick charge feature that allows you to enjoy five hours of listening after just 15 minutes of charging.
Earbud-style headphones range from the disposable models you get on a plane to the ones that are included with your smartphone to high-performance buds that offer sonics rivaling full-size models. Their tiny earpieces rest on the outer ear or need to be inserted into the ear canal, and some models, particularly sport buds, include wings or fins for a more tailored, secure fit.
AAC has some advantages when it comes to latency, but we recommend avoiding this if you care about audio quality. We found high levels of noise and lower than average frequency cutoffs—both unacceptable to audiophiles and younger listeners. Though the sound isn’t as bad as some may make it out to be, the shortcomings are noticeable to the human ear at normal listening volumes.
Open back usually results in more natural sound, but they leak sound in and out. This means you probably can’t use them in a library or a plane flight since the sound of your music will leak out and disturb the people around you. You also can’t use them on loud public places since noise from the outside will disturb your music. Therefore, even though open back would give you more natural reproduction, for these reasons their use is limited to mostly at home or in the office (if you have your own space that is).
The iPhone will drive the headphone fine and make a very nice sound, but the amp will make a big improvement in harmonic extension and soundstage. Use the amp whenever possible. Both Headfonia and I concur that the E07k is a great amp, and probably the best thing you can get for up to twice the price. I’m familiar only with the E07k, the E17, and the E12. I think the E07k beats the E17 (and both are also USB DACs), while the E12 is just an amp, and has a darker sound but with more power for inefficient headphones. The Philips is not inefficient.

Supra-aural headphones or on-ear headphones have pads that press against the ears, rather than around them. They were commonly bundled with personal stereos during the 1980s. This type of headphone generally tends to be smaller and lighter than circumaural headphones, resulting in less attenuation of outside noise. Supra-aural headphones can also lead to discomfort due to the pressure on the ear as compared to circumaural headphones that sit around the ear. Comfort may vary due to the earcup material.
A: What you plug your headphones into can significantly affect their sound, and the quality of the amplifiers built into portable CD/MP3 players is generally awful. It's not their fault: the little guys have to power their electronics and their internal amplifier using a few puny volts. Even some of the better home AV receivers' headphone jacks offer highly variable sound quality.
The Earbuds 500 won’t be available until early 2020, but they might just be worth waiting for. They look to be the natural successor to the SoundSport Free, the company’s first go at truly wireless earbuds, but probably better in every way. The Earbuds 500 will likely have a longer battery life, a smaller charging case and charge via USB-C. They will be sport-focused, too, and a more affordable option to the company’s other new-age wireless earbuds, the Noise Cancelling Earbuds 700.

The Samsung Galaxy Buds are one of the best-scoring portable Bluetooth headphones Consumer Reports has ever tested. That’s all the more impressive given their “true wireless” design, meaning the model doesn’t have a cord connecting the left earbud to the right. That’s the same design scheme popularized by Apple’s AirPods, but our testers say the Galaxy Buds sound dramatically better.

Dirac is mainly for resonance (narrow band) taming and not suitable for normal EQ. Accudio is good. But since the L1 already has a strong bass emphasis, boosting mids or treble just makes the imbalance worse – i.e. the freq. response becomes more ragged and the sound more harsh. To get a smoother sound and better mids and treble, reduce the bass instead.
The E25BT didn’t score quite as high for audio quality as other models on this list, and it lacks some features you’ll find on certain other models, such as water resistance and extended battery life. But if you want a pair of wireless headphones that provide decent sound at a fraction of the cost of its competitors, the E25BT is an appealing option.
The outer shells of in-ear headphones are made up of a variety of materials, such as plastic, aluminum, ceramic and other metal alloys. Because in-ear headphones engage the ear canal, they can be prone to sliding out, and they block out much environmental noise. Lack of sound from the environment can be a problem when sound is a necessary cue for safety or other reasons, as when walking, driving, or riding near or in vehicular traffic.[19]

Sensitivity is a measure of how effectively an earpiece converts an incoming electrical signal into an audible sound. It thus indicates how loud the headphones are for a given electrical drive level. It can be measured in decibels of sound pressure level per milliwatt (dB (SPL)/mW) or decibels of sound pressure level per volt (dB (SPL) / V).[12] Unfortunately, both definitions are widely used, often interchangeably. As the output voltage (but not power) of a headphone amplifier is essentially constant for most common headphones, dB/mW is often more useful if converted into dB/V using Ohm's law:

The QuietComfort 30s are Bose’s wireless in-ear headphones with active noise cancellation, and they’ve set the bar for the category since they were released in 2016. The QuietComfort 30s utilize the same StayHear+ tips as all Bose’s other in-ear headphones and they use the same app as the company’s other QuietComfort headphones. The one caveat is that the QuietComfort 30s are a neckband-style of wireless headphone, so they’re fairly heavy and probably best served for office settings.

There are many good articles here on Headfonia. You could click on Buyers’ Guides and read through those, then click on the Headphones topic header for each individual report. The “process” you go through is learning your own sound preferences, then matching that to the products that are available. It is a process, so you have to learn the major differences. Any shortcuts you take might be OK, but when you buy something that you discover you don’t like, make sure you can return that item.
Headphones are available with high or low impedance (typically measured at 1 kHz). Low-impedance headphones are in the range 16 to 32 ohms and high-impedance headphones are about 100-600 ohms. As the impedance of a pair of headphones increases, more voltage (at a given current) is required to drive it, and the loudness of the headphones for a given voltage decreases. In recent years, impedance of newer headphones has generally decreased to accommodate lower voltages available on battery powered CMOS-based portable electronics. This has resulted in headphones that can be more efficiently driven by battery-powered electronics. Consequently, newer amplifiers are based on designs with relatively low output impedance.