Planar Magnetic Technology for Headphones
A handful of HiFi audio brands are reviving the planar magnetic technology. These companies make headphones using traditional planar drivers that produce a an impressive sound experience.
This paper examines the intrinsic characteristics of a planar magnet device by examining winding inductance, leakage capacitance and conduction losses in winding. A method is also proposed to reduce the parasitic elements.
Low profile or low vertical height
In comparison to traditional wire-wound magnetics, planar magnetic technology offers lower profile and higher efficiency. It also reduces leakage inductance and parasitic capacitance. This allows for a smaller size core to be employed, which reduces the cost of the device. In addition, it does not require any clamping of the magnets. This makes it ideal for power electronic devices.
Another benefit of planar magnetic technology is that it is lighter and more compact than traditional headphones. It can also handle more frequencies without distortion. This is due to the diaphragm, which is flat, used in these devices is often made from a thin film with a conductor trace. This film is able to respond quickly to audio signals and produce high levels of sound pressure with ease.
The audio produced by these devices will be more acoustic and more precise. Many audiophiles love it, especially those who want to listen to music at work or at home. It is important to keep in mind that a planar magnetic driver requires a powered amplifier as well as a digital audio converters in order to perform effectively.
The resulting sound is much more natural and precise than the sound produced by dynamic drivers. Planar magnetic drivers also respond faster to changes in the audio signal, which is why they are the perfect choice for listening to fast music.
Despite their advantages, planar magnet drivers have some drawbacks. Their price is partly due to the massive amount of magnetic material needed for their operation. Another disadvantage is their size and weight which could be an issue when trying to make them portable.
Wide band gap (WBG) devices
Wide band gap (WBG) semiconductors are a class of materials that have better electrical properties than conventional silicon-based devices. They can withstand larger current density as well as higher voltages and lower switching losses. They are therefore suitable for optoelectronics and power electronics applications. Wide band gap semiconductors like gallium nitride and silicon carbide can offer significant improvements in performance, size, and cost. They are also greener than conventional silicon devices. These characteristics make them attractive to aerospace and satellite manufacturers.
Planar magnetic drivers work in the same way as dynamic drivers. A conductor in an electrical circuit moves between two magnets that are fixed when audio signals are passed through them. Planar magnetic drivers, however, employ a flat array of conductors embedded or attached to a thin diaphragm-like film instead of coils. The conductors comprise a set of coils' that sit on the diaphragm and are positioned directly between two magnets. This creates the push/pull effect which triggers the diaphragm's movement.
This technology produces distortion-free music and produces a distinctive pleasant sound. The even distribution of magnetic force over the entire surface of the driver and the absence of a coil sitting behind the diaphragm causes it to move in a uniform manner and quickly, resulting in high-quality, precise sound. The resulting sound is known as isodynamic, orthodynamic, or magnetically-incident.
However, due to their complex design and price headphones that use planar magnetic drivers are typically more expensive than those using other driver technologies. However there are plenty of great, affordable alternatives such as the Rinko by Seeaudio and S12 / Z12 by LETSHUOER that have recently been released.
Power electronics
Planar magnetics are able to disperse heat more effectively than traditional wire wound components. This lets them handle more power without undue strain or audible strain. This makes them perfect for use in headphones. Planar magnetics are more efficient and also offer a higher power density. The technology is especially designed for applications such as electric vehicle charging, battery management, and military systems.
As opposed to dynamic driver headphones which make use of a diaphragm suspended by a voice coil, planar magnetic drivers operate with a completely different premise. A flat array of conductors is placed directly on the diaphragm and when an electromagnetic signal flows through the array, it causes a push-pull interaction with the magnets on both sides of the diaphragm. This creates soundwaves that move the diaphragm and generate audio.
Due to their higher surface-to volume ratio and a higher volume-to-surface ratio, planar magnetic devices are more efficient than conventional magnetics. This means they can disperse more heat, which allows them to operate at higher frequencies of switching without exceeding their maximum temperature ratings. They also have lower thermal sensitivities than wire-wound devices, which means they can be used in more compact power electronic circuits.
Designers need to consider a variety of aspects to optimize a planar booster inductor. These include the core design, winding configurations, losses estimation and thermal modeling. Ideal characteristics of an inductor include low winding capacitance, minimal leakage inductance, and simple integration into a PCB. Furthermore, it must be able to handle high currents and should be tiny size.
The inductor also needs to be compatible with multilayer PCBs with through-hole or SMD packages. The copper thickness must also be sufficiently thin to avoid thermal coupling and reduce eddy-currents between conductors.
Flexible circuit-based planar Winding
In the field of planar magnetic technology the flex circuit-based windings are utilized to create a high-efficiency inductor. They utilize a single-patterned conductor layer on dielectric film that is flexible and can be constructed with a variety foils. A common choice is copper foil, which has exceptional electrical properties and is processed to permit termination features on both sides. The conductors in a flex circuit are connected by thin lines that extend beyond the edges of the substrate, which provides the flexibility required for tape automated bonding (TAB). Single-sided flex circuits are offered in a wide range of thicknesses as well as conductive coatings.
In a typical pair of planar headphones, the diaphragm is placed between two permanent magnets which vibrate in response to the electric signals generated by your audio device. The magnetic fields create the sound wave that moves across the entire diaphragm's surface and creates a piston-like motion that prevents breakups and distortion.
Planar magnetic headphones can reproduce a variety of frequencies, particularly at lower frequencies. This is because they have a larger surface area than traditional cone-type drivers, which allows them to move more air. Furthermore, they are able to reproduce bass sounds with a much greater level of clarity and detail.
Planar magnetic headphones can be costly to produce and require a powered amplifier and DAC to function effectively. In addition, they are larger and heavier than standard drivers, making them difficult to transport and be able to fit into smaller spaces. In addition, their low impedance requires a lot of power to drive them and can add up quickly when you're listening to music at a high volume.
Stamped copper winding
Stamped copper windings are used in planar magnet technology to increase window's efficiency and lower manufacturing costs. The technique involves making grooves into the coil body to support the windings at an exact location in the layer. This method helps prevent coil deformations and improves tolerances. It also reduces the amount of scrap produced during production and enhances quality assurance. This type of planar coil is typically used in contactor coils and relay coils. It is also used in ignition coils as well as small transformers. It is also utilized in devices that have wire thicknesses as high as 0.05mm. The stamping produces a uniform coil with a high current density. It also ensures that the windings are perfectly positioned on the coil body.
Planar magnetic headphones, unlike traditional dynamic drivers that employ a voicecoil conductor in the thin diaphragm, have a flat array of conductors directly bonded to the thin diaphragm. When electronic signals are applied, these conductors vibrate, causing the motion of pistons that produce sound. As a result, planar magnetic headphones provide better sound than other types of audio drivers.
This technology can increase the transducer's bandwidth. This is significant since it lets them operate in a much wider frequency range. It also reduces the power requirements of the driver.
Nevertheless, there are some negatives with this new technology. For instance, it can be difficult to make a thin film diaphragm that is capable of handling the extreme temperatures required by this type of technology. Manufacturers like Wisdom Audio have overcome the issue by introducing a product that is adhesive-free and can withstand temperatures up to 725 degF. This allows them to create top-quality audio without compromising on durability and longevity.