June 23, 2021 / Acoustics news

Pistonic series headphone drivers

Raising the bar

The introduction of the pistonic series of headphone drivers is a very important milestone in the Ole Wolff product lineup. Based on many years of experience and customer feedback, Ole Wolff has developed a set of class-leading drivers for the next generation of headphones.

Introducing Pistonic drivers

What do we mean by “pistonic”?

The word ”Pistonic” has its origins in the way the diaphragms have been developed. The diaphragm is a composition of two very different materials, each having their special mechanical properties. One material for the piston area and another material for the surround.
The piston material must be as stiff and lightweight as possible at any given frequency in the passband and the surround- material on the other hand must be as soft and flexible as possible allowing a very large and linear vertical stroke.
These material properties will ensure optimal signal handling over the full frequency range specified and thereby a crystal clear sound reproduction.

The very stiff dome and the very soft surround create the pistonic movement of the diaphragm.

Key performance parameters

Near perfect pistonic movement of the diaphragm for minimized distortion
High compliance with good damping surround
Biocellulose diaphragm with special Ole Wolff coating material to achieve the best combination of weight and stiffness
Low moving mass to provide the best dynamics
Low THD and high excursion (peak-to-peak >1.6mm) for high fidelity and ANC capabilities
Motor design optimized to achieve the best force factor linearity
Low Intermodulation Distortion (IMD)

Excellent high frequency response

and very low THD

Frequency response extends to well above 20 kHz due to the special biocellulose diaphragm.

SPL (red) and THD (blue).

Designed for high linearity (low THD and IMD)

From the very beginning of the design process focus has been on keeping nonlinearities at a minimum by optimizing both electrical and mechanical parameters and the interaction between the magnetic system and the diaphragm.