ESB 4000 Series 4.28 1.1″/28mm Dome Tweeter

ESB Audio 4000 Series Speakers
The latest model series 4000 (Quattromila), born in 2024, benefits from extensive technical research, which has enabled the use of new materials, previously reserved only for much more expensive speakers. This was also achieved thanks to the parallel development with the top model series 9000 (Novemila), with which the Quattromila series shares several common elements. The main goal of ESB engineers was to achieve a much cheaper product, while maintaining high-quality sound and exclusive design. It is the design that attracts attention at first glance, led by the luxurious grilles of all speakers in a matte black finish, which expresses the aesthetic similarity with the top model series. In all speakers of the Quattromila series, you will also notice powerful neodymium magnets, which guarantee above-standard efficiency and the ability to achieve high sound pressure levels even when using low-power amplifiers. Other noble materials used, such as aluminum or steel, also command respect, but the main advantage of the Quattromila speakers is primarily the sound. This can be defined as “classical”, in other words, genre-neutral and without sound coloration. This fundamentally differs from the higher 5000 series, which is almost competitive in price and whose sound is, on the contrary, more suitable for so-called “light music” (often referred to as music that is easy to listen to), but also jazz or rock. Emphasis was also placed on easy installation in today’s modern vehicles – all speakers have high sensitivity, are also designed for off-axis sound reproduction and, for example, for tweeters, you can choose between three design installation options. The 4000 series includes a total of five individual components for variable assembly of two-way and three-way systems, which, thanks to their sound quality, will impress even the most demanding listeners.

ESB 4.28 tweeters
The 4000 series’ main strengths include tweeters that excel not only in their refined design, but also in their sound. The silk dome with polymer lamination (Sonatex™) creates the perfect balance between weight, stiffness and self-damping. The catenary curvature ensures a wide dispersion of the tweeter. A felt damper under the dome improves the acoustic phase by absorbing reflections from the magnetic structure that reflect off the dome. The high-quality neodymium magnet (N-52) provides excellent resistance to demagnetization and is more than 25% stronger for the same weight than more common lower-class magnets (N-48). The use of this magnet increases efficiency to an extraordinary level, resulting in high power, but also great control of the speaker. The main body is made of glass-filled ABS plastic for excellent strength. An acoustic resistance component inside the vent helps control and dampen the movement of the dome, resulting in reduced distortion and a linear impedance curve for better speaker-amplifier coupling. The pole plate made of extremely low carbon steel is cold forged from a single piece and CNC machined using FEM technology to achieve a perfect geometry. This creates an additional concentration of magnetic force just in front of the voice coil, which focuses the magnetic force where it is needed. This type of manufacturing process ensures perfect flatness, so the plate sits flush with the magnet without reducing the crucial magnetic flux. The copper-clad aluminum voice coil can handle very high power while reproducing music with extreme realism and high dynamics. The voice coil made of copper-clad aluminum wire is very light and has excellent heat dissipation. At the same time, it provides maximum sensitivity and extends the high-frequency response of the speaker. The luxurious stainless steel grille features a unique acoustic lens shape that allows sound to be reproduced not only on-axis but also to the sides. This is very useful in automotive installations, where speaker placement often results in off-axis listening. The low resonance frequency ensures optimal frequency range even in 2-way systems. Two types of removable tweeter housing are included for variable installation options.