Transducer technologies employed much less commonly for headphones include the Heil Air Motion Transformer (AMT); Piezoelectric film; Ribbon planar magnetic; Magnetostriction and Plasma-ionisation. The first Heil AMT headphone was marketed by ESS Laboratories and was essentially an ESS AMT tweeter from one of the company's speakers being driven at full range. Since the turn of the century, only Precide of Switzerland have manufactured an AMT headphone. Piezoelectric film headphones were first developed by Pioneer, their two models used a flat sheet of film that limited the maximum volume of air movement. Currently, TakeT produces a piezoelectric film headphone shaped similarly to an AMT transducer but, which like the Precide driver, has a variation in the size of transducer folds over the diaphragm. It additionally incorporates a two way design by its inclusion of a dedicated tweeter/supertweeter panel. The folded shape of a diaphragm allows a transducer with a larger surface area to fit within smaller space constraints. This increases the total volume of air that can be moved on each excursion of the transducer given that radiating area.
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.

The impedance of headphones is of concern because of the output limitations of amplifiers. A modern pair of headphones is driven by an amplifier, with lower impedance headphones presenting a larger load. Amplifiers are not ideal; they also have some output impedance that limits the amount of power they can provide. To ensure an even frequency response, adequate damping factor, and undistorted sound, an amplifier should have an output impedance less than 1/8 that of the headphones it is driving (and ideally, as low as possible). If output impedance is large compared to the impedance of the headphones, significantly higher distortion is present.[11] Therefore, lower impedance headphones tend to be louder and more efficient, but also demand a more capable amplifier. Higher impedance headphones are more tolerant of amplifier limitations, but produce less volume for a given output level.


These early headphones used moving iron drivers,[7] 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.

Telephone headsets connect to a fixed-line telephone system. A telephone headset functions by replacing the handset of a telephone. Headsets for standard corded telephones are fitted with a standard 4P4C commonly called an RJ-9 connector. Headsets are also available with 2.5 mm jack sockets for many DECT phones and other applications. Cordless bluetooth headsets are available, and often used with mobile telephones. Headsets are widely used for telephone-intensive jobs, in particular by call centre workers. They are also used by anyone wishing to hold telephone conversations with both hands free.


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.
Transducer technologies employed much less commonly for headphones include the Heil Air Motion Transformer (AMT); Piezoelectric film; Ribbon planar magnetic; Magnetostriction and Plasma-ionisation. The first Heil AMT headphone was marketed by ESS Laboratories and was essentially an ESS AMT tweeter from one of the company's speakers being driven at full range. Since the turn of the century, only Precide of Switzerland have manufactured an AMT headphone. Piezoelectric film headphones were first developed by Pioneer, their two models used a flat sheet of film that limited the maximum volume of air movement. Currently, TakeT produces a piezoelectric film headphone shaped similarly to an AMT transducer but, which like the Precide driver, has a variation in the size of transducer folds over the diaphragm. It additionally incorporates a two way design by its inclusion of a dedicated tweeter/supertweeter panel. The folded shape of a diaphragm allows a transducer with a larger surface area to fit within smaller space constraints. This increases the total volume of air that can be moved on each excursion of the transducer given that radiating area.
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.
In terms of juice, the Elite 65t offer 5 hours of battery life — matching the AirPods — and the included charging case adds two refills on the go. Jabra also matches many of the best features we’ve seen elsewhere in the fully wireless space, with the company’s Sound+ app that lets you adjust settings like equalization, or whether you want to use your phone’s built-in smart assistant (Siri on iOS, Google Assistant on Android) or Amazon Alexa. Sensors built into the headphones can be set to play and pause music when you remove the buds, and they can even be set to pipe in different levels of ambient sound, which is great for hearing announcements on the plane or your office mate.
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.
The rule that I use is that the bigger the size of the headphone, the bigger the need for amplification. Of course factors like driver sensitivity and impedance will matter, but the general rule of thumb is, use a dedicated headphone amplifier for a full size headphone. Even a portable amplifier can be enough, depending on the type of the headphones.
That amp, if in good working condition, has 100 times the potential sound quality that those 2 headphones can play. You could improve the sound somewhat with a careful EQ, since the Marantz will have power reserve to spare. But I’d try to find a better headphone, and there are some bargains out there. If I were suggesting an ortho, I’d say get the lower price Mad Dog, which will give you great audiophile sound with the Marantz.

In early powered radios, the headphone was part of the vacuum tube's plate circuit and carried dangerous voltages. It was normally connected directly to the positive high voltage battery terminal, and the other battery terminal was securely grounded. The use of bare electrical connections meant that users could be shocked if they touched the bare headphone connections while adjusting an uncomfortable headset.
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