How Do
Magnet Planar Headphones Work?
If you've not yet tried a pair headphones that utilize magnetic drivers with planar design it can be difficult to wrap your mind around how they work. Contrary to the voicecoil motor that drives a stiff cone back and forward the planar magnetic drivers use two flat magnets sandwiching thin diaphragms printed with conductors.
The Diaphragm
Magnet planars are flat pieces of flexible film, in contrast to traditional dynamic headphone drivers with a dome or cone shaped diaphragm. The film is made of conductors which react to magnets placed across the membrane. When the electrical signal flowing through these wires changes the magnetic field generated by the magnets causes the diaphragm to react and move. The movement produces sound waves that you then hear.
The diaphragm in the human body is a dome-shaped muscle membrane that separates the thoracic (chest) and abdominal cavities. It is the primary respiration muscle and is involved in the process of inspiratory action (exhaling air) like breathing and coughing, sneezing, crying, laughing, vomiting, and parturition. The diaphragm is also vital for expulsive actions, such as defecating and urinating and pushing the fetus out during delivery.
Due to the ultra-light and thin nature of a planar diaphragm it is more flexible to changes in audio signal than dynamic drivers. This gives planar magnetic headphones sound that is more delicate and precise than the sound you get from a dynamic driver.
One of the disadvantages of planar magnetic headphones is that they can have a little more leakage than their dynamic counterparts, particularly at higher volume. This is due to the movement of the diaphragm within a planar magnetic headphone causes some of the audio to be pushed outwards and then towards the listener.
This isn't a problem if you only use headphones in quiet areas or when watching movies however it can be a nuisance for active listening and public use. Thankfully, there are some very good options available to reduce the amount of leakage such as the Audeze LCD-4 or HiFiMAN Sundara. In addition, some brands such as Wisdom Audio are at the forefront of advancing PMD technology and have been working hard to address the issues that come with this style of headphone. They have invented numerous innovations that you can see on their products. For example, their new flexible circuit-based planar winding eliminates the limitations of stamped copper windings and gives them a better utilization factor.
The Conductors
Conductors are what connect the diaphragm to the magnets and they are the ones responsible for creating the sound that you hear. They are typically made of a combination of copper and aluminum. They are then wrapped around the central magnetic core which is enclosed by the diaphragm, and is held by the frame of the headphone. The magnetic core may be made of any material, but it is typically Neodymium. The core is the main component of any planar magnetic audio driver. It consists of several nested layers of an helix that is circular with a diameter of 10-20mm.
Planar magnetic drivers have the advantage of creating a wider soundstage than their more dynamic counterparts. This is because when an audio signal arrives in the diaphragm, it vibrates across the entire area instead of the tiny space that is connected to the voice coil. This greater surface area results in lower distortion levels, especially at higher volumes.
Another key feature of a magnet planar is its ability to respond quickly to the changes in the audio signal. This allows for a greater range of frequencies to be reproduced and more authentic sound. Audiophiles who love music with different instruments and vocals will appreciate this feature.
The stacked design of planar magnetics reduces the variability of part-to-part which makes them suitable for critical applications that require high reliability. As compared to wirewound magnetics, they offer improved consistency with lower magnetic field distortion, which is vital to the performance of any electronic device.
The Magnets
As the name suggests the word magnet refers to an element that has magnetic properties. It can create an attractive or a repulsive force on certain substances such as nickel, iron, cobalt and some steels. It can also attract and repel certain electrical conductors. This phenomenon is referred to as magnetism. It can be produced by permanent, electromagnets or temporary magnets. Magnets can be utilized in a wide range of applications and are utilised in many different types of devices including electronic devices such as headphones laptop computers, mobile phones and car audio systems.
Planar magnetic
driver planar technology, unlike traditional dynamic or balanced armature drivers, which push an extremely rigid and stiff diaphragm using a voice coil to create the sound wavefront, employs an extremely thin and flexible diaphragm. This diaphragm vibrates and creates a flat wavefront rather than a focused spherical one, as is typical in most headphones and speaker. This results in a more spacious and
Magnet Planar cleaner soundstage, and is well-known for its deep bass.
The biggest drawback to planar magnetic drivers is that they need plenty of power to move the massive magnets inside them which makes them heavier and heavier than other kinds of headphone drivers. Many planar magnetic drivers need an amplifier to function properly.
The amplifier should be designed to match the power output of the planar magnetic driver in order to give the best listening experience. The amplifier must also have a high input impedance to allow it to be able to drive the planar magnetic driver at its maximum output.
The planar magnetic drive is typically designed as either dipole, which radiates equally and in opposing phases in front and behind the speaker (like ESLs), or a monopole, which radiates only in the forward-facing direction (more similar to traditional headphones). The most popular design of a planar magnetic driver is a bipole, with alternating poles on the north and south. Its shape permits it to be easily made into a single metal piece and creates a solid field in the center of the faceplate.
Due to their size and efficiency they have a lower distortion than other types of headphone drives. They are commonly used in high-end headphone systems where sonic accuracy is crucial. They can also be found in audio equipment for professionals like microphones and loudspeakers. Due to their unique construction, they are also suitable for medical imaging and other delicate applications that require a high degree of precision.
The Seal
To ensure that planar drivers function optimally, they must be sealed in a tight and precise manner. A tiny leak can have a significant impact on the quality of sound and could cause distortion. It requires an enormous amount of effort to create the right seal for planar driver.
Planar magnetic headphones, unlike other headphone designs, must not have gaps within the enclosure for acoustics. This is because gaps cause the diaphragm to resonate with different frequencies at the same time. This is known as crosstalk, and can cause the entire audio quality to suffer greatly.
Rubber ring seals are the most commonly used seals used in headphones that are planar. This type of seal prevents air leaks very effectively. It is also extremely robust and lasts for an extended period of time. It is important to remember that this type of seal can sometimes produce hollow sounds. If you plan to use a planar magnet headphone, it's important to select a high-quality seal.
The liquid crystal display (LCD) seal is a different alternative for a magnetic planar driver. This is an advanced seal designed to prevent gaps from forming. It also can stand up to pressures of a great deal.
