Introduction

• Many ordinary headset users think that “Audiophiles” are a “crazy ” group. If you have a group of friends who are obsessed with HiFi headphones, they tell you how amazing the sound of electrostatic headphones is, but when you look at the price, “Why it is so expensive?”

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• Judging the quality of headphones from a single unit is one-sided. The key to evaluating the sound quality of the earphones should be measured from various aspects such as sound details, positioning, clarity of hierarchy, high-frequency extension, low-frequency diving degree, and whether the transition of all-around frequencies is natural and smooth, etc.

• There are four common earphone driver units--dynamic or 'moving coil', balanced armature, planar magnetic, and electrostatic (EST). Different units present different sound effects and quality. 

Categories of earphones on Markets

• In addition, manufacturers in the audio industry have constantly launched various earphones. BA, DD, hybrid DD+BA, DD+BA+Planar Magnetic, and latest popular EST type, etc. Of course, the most expensive of these earphones is electrostatic earphones.

How does the EST driver work?

Comparison of three types of drivers

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   The working principle of the electrostatic unit: There is a diaphragm and two electrodes in the unit, and high DC voltage is applied to these three elements to make them electrically charged. After that, the audio signal is transmitted to the polar plate through the equivalent sound pressure circuit, and the two polar plates and the diaphragm vibrate according to the same-sex repulsively and the opposite sex attracts each other.

       Diaphragm: The electrostatic diaphragm, usually a PET film membrane, can be made extremely thin and light, and the thickness is generally measured in microns. After being electrically polarized, the thin diaphragm can vibrate quickly under electromagnetic bias, bringing excellent transient response and detailed analysis. Electrostatic diaphragm earphones are generally expensive because of their high cost and complex technology and are generally not reproducible.

        Electrodes: In a static electrostatic unit, the amount of charge and the diaphragm maintain a relatively stable state. When the audio signal is input, the electrode produces electrical vibration to the diaphragm, which is different from the moving coil(dynamic driver) unit. A parallel plate can achieve a complete linear drive (that is, the positive correlation is expressed as a straight line), but the moving coil unit cannot achieve it. Due to the large area of the electrostatic shock membrane and more air involved in the vibration, there are generally many hollow parts on the electrodes to ensure unobstructed airflow.

       The structure of the electrostatic unit is simple, but the technical requirements are extremely strict. Although the electrostatic unit can theoretically output top high-fidelity sound quality, due to technical reasons, there are few brands or manufacturers that do not have enough power to produce electrostatic earphones, so the mainstream headset products on the market are still dominated by the dynamic driver and balanced armature unit headphones. 

Pros and Cons of electrostatic earphones

• As many consumers and experts say, like any other types of headphones, they also have pros and cons although we do need to admit electrostatic headphones are so far the best thing an audiophile can have.
• The main benefit of these is an extremely high-quality sound. Another benefit is the more “advanced” way of operating, without conductors, with the diaphragm moving exclusively by itself.
• Speaking of bad sides, the first one would be the price. Even when you search for the cheapest electrostatic earphones, you will see that they may not be so budget-friendly as some other types are. Besides, since they require an amplifier, even the cheapest model is more expensive than some other headphones. 
• Frankly speaking, we may say that these are truly great headphones if you are not limited by your budget. However, do keep in mind that the price range is big, and sometimes, if you are lucky enough, you can get a decent pair of used ones at an affordable price.

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• Now there is a Chi-fi brand that released its comparatively budget-friendly EST IEM-TRI Starshine. TRI's first flagship electrostatic headset is called Starlight, and the official price is $799, which is also an electrostatic earphone. More details to check here.
• Starshine is equipped with Knowles double BA units plus two Denmark SONION electrostatic units. Makes the electrostatic force point field completely uniform, and the linear drive has a fast response speed. 

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• Able to reproduce all kinds of tiny details with extremely low distortion. The sound quality is transparent and high-quality, the instrument density and separation are pretty good, and the outline is clear and does not overwhelm the vocal. 
• The low frequency is not muddy, and the overall sound is clean and loose, durable and delicate, but it is more thrusting. 
• In appearance, the headsets are made of epoxy resin and rich irregular face plate texture colors. The sea and the earth are integrated into a seamless process, And the cavity is made of gentle and comfortable German skin-friendly resin.