High Frequency Unit

The EVO series concept originated from the same thorough research and development processes that characterized Wharfedale’s flagship Elysian project. It was specifically designed to bridge the gap between affordability and high-end performance. A notable feature of this series is the EVO AMT (Air Motion Transformer) high-frequency unit.

A Distinctive Approach to High Frequencies

AMT Tweeter for Precision and Detail: In developing the new EVO 5 series, Wharfedale has further evolved the cutting-edge Air Motion Transformer (AMT). The AMT is a type of high-frequency driver used in speakers, known for its exceptional accuracy, speed, and low distortion compared to traditional dome treble units.

Instead of using a conventional dome or cone to push air forward, an AMT uses a pleated diaphragm made of an ultra-thin, lightweight material (often a polymer film). Strong magnets are positioned on either side of the diaphragm, creating a powerful magnetic field. When an audio signal is passed through the conductive traces, the diaphragm is energized, causing the pleats to contract and expand. As the pleats move, they "squeeze" and "expand" the air between them, pushing it out in a highly controlled and efficient manner. This method allows the AMT to move four times more air than a traditional dome tweeter of the same surface area, leading to lower distortion (since the diaphragm moves less than a typical dome or ribbon), faster transient response (due to the lightweight material and minimal movement), wider frequency range and better dispersion.

Absorption and Damping Enhancements

A new sound-absorbing material, Silentweave, has been added to the cavity behind the diaphragm to reduce sound wave reflection and sound coloration inside the speaker. This material, a combination of cotton and felt fiber, was specially developed for the EVO 5 series.

All EVO 5 drive units benefit from a new acoustic damping frame called ResoFrame, made from elastomer and visible as a cog-like shape within the driver’s front panel. In the case of the AMT, an additional elastomer damping gasket between the diaphragm and the front plate further reduces mechanical resonances and smooths the response, especially in the important lower treble band.

These internal acoustic enhancements minimize unwanted sound coloration, ensuring a purer, more natural sonic signature. This smoother treble response delivers a listening experience that is crisp, controlled, and devoid of harshness.

Lower-Midrange and Bass Refinements for Unparalleled Vocal Reproduction

Enhanced Midrange: A new technique, labeled Resoseal, sees a thin mass ring of elastomer applied to the rear of the cone where it meets the surround. This further optimizes midrange frequency response, allowing vocals to sound richer, more natural, and more emotionally engaging. This subtle yet critical enhancement ensures a refined and immersive listening experience.

Reengineered Cabinetry for Superior Resonance Control

Each model in the EVO 5 series now features an optimally increased internal cabinet volume. The expanded cabinet volume contributes to deeper bass extension and improved overall sound dispersion, creating a more immersive and expansive audio field.

The inclusion of a hybrid plinth, which combines metal and wood elements of the cabinet’s details, enhances structural integrity and reduces unwanted vibrations. This innovative base ensures that sound remains clean and uncolored, free from external resonance artifacts.