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.
A balanced armature is a sound transducer design primarily intended to increase the electrical efficiency of the element by eliminating the stress on the diaphragm characteristic of many other magnetic transducer systems. As shown schematically in the first diagram, it consists of a moving magnetic armature that is pivoted so it can move in the field of the permanent magnet. When precisely centered in the magnetic field there is no net force on the armature, hence the term 'balanced.' As illustrated in the second diagram, when there is electric current through the coil, it magnetizes the armature one way or the other, causing it to rotate slightly one way or the other about the pivot thus moving the diaphragm to make sound.
The QuietComfort 20 headphones have been around for years and years; and they’re essentailly an in-ear alterative to Bose’s QuietComfort 25. They offer the same great active noise-cancellation that the company is known for, just in a traditional wired and in-ear form factor. The QuietComfort 20 can also be switched to an “Aware” (aka ambient) mode, so you can better hear the world around you.
Recently released this summer, the Headphones 700 are the best wireless over-ear headphones that Bose has to over. The combine the best-in-class noise-cancellation with great audio quality. Other than the design overhaul, the biggest difference from the QuietComfort 35 II is that the Headphones 700 have a significantly upgraded microphone array. This allows the headphones to have a wonderful tranparancy mode (or ambient listening mode), and makes maybe the best headphones you can buy for call quality.
Portability can mean many things, such as appearance in public, having a secure fit so the headphone doesn’t shift off of your ears, amount of isolation from ambient noise (including active noise canceling), whether the headphone can be worn around the neck when not listening or it requires a carry case, and when extra amplification is required, whether a suitable amp can be found that’s OK to carry along with the portable music player.
While Apple’s AirPods get a lot of attention for how well they work with other Apple products, there’s actually a more affordable option that’s just as tightly integrated: the Beats BeatsX Earphones. Apple owns the Beats brand, and it’s built the BeatsX earphones with the same W1 chip that’s in the AirPods. That means that the user experience is virtually identical – iOS makes it super easy to pair them with any iPhone or iPad. Our favorite part is they have a Fast Fuel feature, so when your battery is low, plugging them in for five minutes provides two hours of talk time. We’re also big fans of the COWIN E7 Headphones. They’re wireless, they’ve got on-board noise cancellation, and they can last up to 30 hours on a single charge. The E7’s have an impressive spec sheet for any price point, but the fact that they’re so affordable makes them an even better value. If you’re looking for affordable over-the-ear headphones that don’t make any compromises, this is the pair to get.
An electret driver functions along the same electromechanical means as an electrostatic driver. However the electret driver has a permanent charge built into it, whereas electrostatics have the charge applied to the driver by an external generator. Electret and electrostatic headphones are relatively uncommon. Original electrets were also typically cheaper and lower in technical capability and fidelity than electrostatics. Patent applications from 2009-2013 have been approved that show by using different materials, i.e. a "Fluorinated cyclic olefin electret film", Frequency response chart readings can reach 50 kHz at 100db. When these new improved electrets are combined with a traditional dome headphone driver, headphones can be produced that are recognised by the Japan Audio Society as worthy of joining the Hi Res Audio program. US patents 8,559,660 B2. 7,732,547 B2.7,879,446 B2.7,498,699 B2.
The thermoacoustic effect generates sound from the audio frequency Joule heating of the conductor, an effect that is not magnetic and does not vibrate the speaker. In 2013 a carbon nanotube thin-yarn earphone based on the thermoacoustic mechanism was demonstrated by a research group in Tsinghua University. The as-produced CNT thin yarn earphone has a working element called CNT thin yarn thermoacoustic chip. Such a chip is composed of a layer of CNT thin yarn array supported by the silicon wafer, and periodic grooves with certain depth are made on the wafer by micro-fabrication methods to suppress the heat leakage from the CNT yarn to the substrate.
The Bose QuietComfort 35 II is arguably still the most comfortable pair of noise-canceling headphones you can buy. Released in the summer of 2018, you can think of the QuietComfort 35 II as simplified, less sophisticated and more affordable version of the new Headphones 700. The lack the transparency mode, superior call quality, USB-C charging port and on-ear gesture controls, but they still boast really impressive noise-canceling skills. The also have the tradional foldable design — it folds more compactly — that many travelers really like.
Anyway, I’m looking for comfortable headphones for casual listening from my mobile phone, and so far I’m uncomfortable with portables. I have tried many portables in multiple stores, they sweat my ears after few minutes, and their small size never cover my ears properly. Recently I have experienced one of Clarion headphone (dunno which series, its price around Rp 99.000), while its big ear cushion cover my ears properly, I felt too much pressure on the area below my ears, probably due to its weight..
Those who buy either of these headphones are in for a treat. Our reviewer didn’t hold back in their assessment of these cans’ ability to fully realize every detail of a recording, noting their “warm and rigid bass, a midrange that dips close to the ruddy colors of analog tape saturation (without sacrificing an ounce of detail), and a laser tight response up top that helps illuminate vivid clarity and granular instrumental texture across the board.”
These early headphones used moving iron drivers, with either single-ended or balanced armatures. The common single-ended type used voice coils wound around the poles of a permanent magnet, which were positioned close to a flexible steel diaphragm. The audio current through the coils varied the magnetic field of the magnet, exerting a varying force on the diaphragm, causing it to vibrate, creating sound waves. The requirement for high sensitivity meant that no damping was used, so the frequency response of the diaphragm had large peaks due to resonance, resulting in poor sound quality. These early models lacked padding, and were often uncomfortable to wear for long periods. Their impedance varied; headphones used in telegraph and telephone work had an impedance of 75 ohms. Those used with early wireless radio had more turns of finer wire to increase sensitivity. Impedance of 1000 to 2000 ohms was common, which suited both crystal sets and triode receivers. Some very sensitive headphones, such as those manufactured by Brandes around 1919, were commonly used for early radio work.