Once you’ve got that all order, to put a cherry on top it would be ideal for the amp to play nice with my laptops (PC at work, Mac at home) *and* my *iPhone* 4S.  I haven’t found a headunit that works with PCs and iDevices.  If one doesn’t exist it would be a big plus for the amp to include inputs so I can get digital sound out of my iPhone (with the Pure i20 or its ilk) and into my headphones.
Smaller earbud type earpieces, which plugged into the user's ear canal, were first developed for hearing aids. They became widely used with transistor radios, which commercially appeared in 1954 with the introduction of the Regency TR-1. The most popular audio device in history, the transistor radio changed listening habits, allowing people to listen to radio anywhere. The earbud uses either a moving iron driver or a piezoelectric crystal to produce sound. The 3.5 mm radio and phone connector, which is the most commonly used in portable application today, has been used at least since the Sony EFM-117J transistor radio, which was released in 1964.[9][10] Its popularity was reinforced with its use on the Walkman portable tape player in 1979.

The Soundsport Free, released in the fall of 2017, are Bose’s first truly wireless earbuds. They utilize the same StayHear+ Sport tips as the company’s other in-ear headphones, making them naturally more sweat-resistant and more secure than AirPods. They work with the Bose Connect app, which is pretty basic but does have a “Find My Buds” feature that, when enabled, can help you find your earbuds should you misplace them.

We use a commercially-available Bluetooth high-def interface with an S/PDIF output to test the Bluetooth output of four flagship phones. This way, we’re able to record test signal output and compare the datasets with our in-house analysis software. We kicked the tires on a 96kHz/24-bit test file to see how Bluetooth handled high-bitrate music, as well as normal 44.1kHz/16-bit files to see how each codec treated CD-quality streaming audio. We then measured the recorded sample against the original file. We used both lograrithmic sine sweeps, and complex signals like square waves in order to provide a more realistic set of tests for how people actually use Bluetooth headphones.

Their combination of dual balanced-armature drivers matched with a dynamic driver to pump up the lower end are kind of engineering normally found on products that cost more than double the price of the 1Mores. Even the smaller details are very well ironed out, such as Kevlar-wrapped cables that increase resistance to wear while simultaneously reducing tangles.

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.

Despite big promises from Bluetooth’s only Hi-res codec, the standard doesn’t really deliver at best, and it falls far short with its basic 330kbps setting. Both the 660kbps and 990kbps connections offer decent quality, but the 330kbps setting has a lot of noise—and a comparatively poor frequency response with higher-def content. You probably won’t hear it, but it definitely falls short of the marketing.
Ok, it’s been a month and a lot of new experience. I’ve auditoned ATH M-50 (clamp’s too tight; they sweat my ears just from few minutes of exposure) and Senn HD 600 (the velour pad is amazingly comfortable & size is ok). So, long story short, now I can refine my search to: circumaural&non-pleather/foam pads, which brought me to Senn HD 439 (cloth) & 518 (velour).

A. It depends. Noise-cancelling headphones use active technology to play unique frequencies that block outside noises, and depending on which model you buy, the battery can last anywhere from 15 to 40 hours. If you’re using a set of wireless headphones, the battery will be used for both noise cancellation and wireless connectivity, so expect the battery to deplete faster if you’re using both.
Active noise-cancelling headphones use a microphone, amplifier, and speaker to pick up, amplify, and play ambient noise in phase-reversed form; this to some extent cancels out unwanted noise from the environment without affecting the desired sound source, which is not picked up and reversed by the microphone. They require a power source, usually a battery, to drive their circuitry. Active noise cancelling headphones can attenuate ambient noise by 20 dB or more, but the active circuitry is mainly effective on constant sounds and at lower frequencies, rather than sharp sounds and voices. Some noise cancelling headphones are designed mainly to reduce low-frequency engine and travel noise in aircraft, trains, and automobiles, and are less effective in environments with other types of noise.

I think it’s fair to compare the Grados and HD598, but the M50 is very different and seems not to fit in that comparison. The DT770 is a better comparison to the M50, although the 770 is a better more expensive item. A long time ago I had a Grado 325 and a Sennheiser HD565 – very similar, very enjoyable. Today for that type of sound I might choose the Soundmagic HP100.
The Galaxy Buds produce exemplary audio quality packed into a pair of unobtrusive earpieces, complete with easy-to-use touch controls for playback, volume, and skipping tracks. According to Samsung, they have a 6-hour battery life and come with a powered carrying case that will recharge the earphones for up to 7 additional hours of playback on the go. The case itself can be charged with a wireless charging mat, and it’s particularly small compared with the cases that come with many true wireless models.

Cable dressing and length: Most stereo headphones have just one cable, usually attached to the left earpiece (sometimes called single-sided cabling). Some models -- and all earbuds -- use a Y-cable that connects to both earpieces (double-sided). The actual cable plug, meanwhile, is usually one of two designs: a straight I-plug or an angled L-plug; the latter may be useful if your portable player has a side- or bottom-mounted headphone jack.
There’s a lot of debate in the headphone world about wireless audio. Wireless standards like Bluetooth are capable of making music sound great, but because Bluetooth relies on data compression, it will never sound quite as good as a wired connection. The big question is, with the improvements in Bluetooth, can anyone tell the difference anymore between Bluetooth audio and wired audio? We’re skeptical that the difference is meaningful, so here’s our best advice: if you’re an audiophile who cares about hearing music in high fidelity, you’ll probably be better off with a set of wired headphones; if you need everything to sound great but prefer the convenience of wireless connections, go for a pair of Bluetooth headphones.

While iPhone users can expect that their phones are missing essential parts to look good, AAC is one of those codecs that maybe cut a few too many bits out of its data transmission. By using an aggressive psychoacoustic model of compression, AAC seeks to cut data where you wouldn’t normally be able to hear it anyway—but it gets a little too aggressive at times.
A. Near-field communication, better known as NFC, is a wireless connectivity protocol similar to Bluetooth. NFC uses less power than Bluetooth and is faster when pairing devices, but it only has a range of about four inches. Some headphones use NFC technology to drive the process of pairing headphones with smartphones, but because of the range, it’s not used to transmit sound. While both Android phones and iPhones include NFC chips, it’s not accessible in Apple devices, so if you want a pair of headphones with NFC, you’ll need to own an Android phone to take advantage of the faster pairing.
These headphones pack about 16 hours of battery life, which ought to be enough for a whole day or more, but if not, there’s always the option of using an analog cable instead. An external switch lets you turn the noise cancellation on and off. Make no mistake, these might be aimed at kids, but the quality of construction, selection of materials, and color choices give them an appearance that will still appeal to your young charges long after they’ve outgrown their Disney phase (some of us still haven’t).
Audiophiles generally agree that if you’re passionate about music, and you have a listening space that is relatively free of outside sounds, nothing beats a really good set of open-back headphones. As far as we’re concerned, you won’t find a set of open-back headphones that manage to combine superb sound quality and a reasonable price than the Sennheiser HD6XX/HD650. To be clear, these are not exactly the same models. The HD6XX is a run of the HD650 with a lower price from Massdrop, and a few physical changes, but when it comes to their audio chops, they’re identical.

Once you’ve got that all order, to put a cherry on top it would be ideal for the amp to play nice with my laptops (PC at work, Mac at home) *and* my *iPhone* 4S.  I haven’t found a headunit that works with PCs and iDevices.  If one doesn’t exist it would be a big plus for the amp to include inputs so I can get digital sound out of my iPhone (with the Pure i20 or its ilk) and into my headphones.

Generally, headphones are able to reproduce richer low-end audio, since they have larger drivers than earphones and they don't rely on an in-ear seal to deliver sound. Some listeners also find headphones more comfortable to wear, and easier to put on and take off, than they do earphones. This naturally means that headphones are bulkier, and less suited to the gym.
Sports headphones are among the most popular types of headphones and the best ones are now wireless. Sweat-resistant or even totally waterproof, they can be used at the gym or for running or biking. Some are have an open or semi-open design to let some sound in for safety reasons (so you can hear traffic noise). However, other models have a sealed, noise-isolating design.
A headset is a headphone combined with a microphone. Headsets provide the equivalent functionality of a telephone handset with hands-free operation. Among applications for headsets, besides telephone use, are aviation, theatre or television studio intercom systems, and console or PC gaming. Headsets are made with either a single-earpiece (mono) or a double-earpiece (mono to both ears or stereo). The microphone arm of headsets is either an external microphone type where the microphone is held in front of the user's mouth, or a voicetube type where the microphone is housed in the earpiece and speech reaches it by means of a hollow tube.

Using headphones at a sufficiently high volume level may cause temporary or permanent hearing impairment or deafness. The headphone volume often has to compete with the background noise, especially in loud places such as subway stations, aircraft, and large crowds. Extended periods of exposure to high sound pressure levels created by headphones at high volume settings may be damaging to hearing;[25][26] Nearly 50% of teenagers and young adults (12 to 35 years old) in middle and high income countries listen to unsafe levels of sound on their personal audio devices and smartphones.[27] however, one hearing expert found in 2012 (before the worldwide adoption of smartphones as the main personal listening devices) that "fewer than 5% of users select volume levels and listen frequently enough to risk hearing loss."[28] The International Telecommunication Union recently published "Guidelines for safe listening devices/systems" recommended that sound exposure not exceed 80 decibels, A-weighted dB(A) for a maximum of 40 hours per week.[29] The European Union have also set a similar limit for users of personal listening devices (80 dB(A) for no more than 40 hours per week) and for each additional increase of 3-dB in sound exposure, the duration should be cut in half (83 dB(A) for no more than 20 hours, 86 dB(A) for 10 hours per week, 89 dB(A) for 5 hours per week and so on. Most major manufactures of smartphones now include some safety or volume limiting features and warning messaging in their devices.[30][31] though such practices have received mixed response from some segments of the buying who favor the personal choice of setting their own volume levels.

Hearing risk from headphones' use also applies to workers who must wear electronic or communication headsets as part of their daily job (i.e., pilots, call center and dispatch operators, sound engineers, firefighters, etc.) and hearing damage depends on the exposure time. The National Institute for Occupational Safety and Health (NIOSH) recommends sound exposure not exceed 85 dB(A) over 8 hour work day as a time-weighted average.[35] NIOSH uses the 3-dB exchange rate often referred to as "time-intensity tradeoff" which means if sound exposure level is increased by 3 decibels, the duration of exposure should be cut in half. NIOSH published several documents targeted at protecting the hearing of workers who must wear communication headsets such as call center operators,[36] firefighters,[37] and musicians and sound engineers.[38]

In the professional audio sector, headphones are used in live situations by disc jockeys with a DJ mixer, and sound engineers for monitoring signal sources. In radio studios, DJs use a pair of headphones when talking to the microphone while the speakers are turned off to eliminate acoustic feedback while monitoring their own voice. In studio recordings, musicians and singers use headphones to play or sing along to a backing track or band. In military applications, audio signals of many varieties are monitored using headphones.