Technology

ABS — The Truth

How Kawai solved the fundamental problem of wood in piano actions — and why composite materials represent a generational leap in piano performance.

Every Innovative Idea Began with a Problem

For Kawai piano craftsmen in the 1960s, the problem centered around wood. While certainly ideal for all of the important sound-producing elements of a piano, wood was woefully inadequate for many of the critical components found in a piano's action.

First, wood was susceptible to breakage when subjected to continual high stress. But far more troublesome was wood's tendency to shrink and swell dramatically with changes in climate. Lacking alternatives, piano makers simply accepted the shortcoming of wood, forcing piano technicians to “treat the symptoms” by replacing failed wood parts and making continual adjustments.

Kawai craftsmen remained troubled — they knew that these inherent weaknesses of wood posed a serious threat to the quality and character of a piano's touch and tone.

The Symptoms of Wood in Piano Actions

Susceptibility to Breakage

Wood components subjected to the continuous high-stress cycling of piano playing are vulnerable to cracking and fracture, leading to costly repairs.

Shrinking and Swelling

Changes in humidity cause wood parts to expand and contract, altering the precise geometry of the action and degrading both tone and touch consistency.

Ongoing Maintenance

The instability of wood forces regular adjustments by technicians. Without continuous service, a wooden action will drift out of regulation, compromising performance.

The Solution — ABS Composite Materials

Kawai's solution was revolutionary: replace the mechanical components of the piano action with ABS (Acrylonitrile Butadiene Styrene) composite materials. Unlike wood, ABS is virtually impervious to changes in humidity — it doesn't shrink, swell, or warp. This fundamental stability means that a Kawai piano action maintains its precise regulation year after year, regardless of climate.

First introduced in 1970, Kawai's ABS composite parts represented the fourth major evolution of the piano action. Over decades of use in homes, concert halls, and institutions worldwide, ABS parts have proven their superiority through performance — not just laboratory testing.

The Evidence

Kawai's composite materials have been subjected to rigorous independent testing:

→ABS-Carbon parts are over 50% stronger than conventional wooden parts
→Carbon fiber infusion increased strength by 90% over standard ABS-Styran
→The Millennium III Action is approximately 25% faster than a conventional wooden action
→Composite parts show no dimensional change after decades of temperature and humidity cycling

ABS-Carbon — The Next Generation

Building on decades of ABS innovation, Kawai developed ABS-Carbon — a new composite material created by infusing carbon fiber into ABS-Styran. This next-generation material is incredibly sturdy and rigid, allowing Kawai to make action parts lighter without sacrificing strength. The result is the Millennium III Action: faster, stronger, and more precise than any wooden action ever built.

The Truth About Composite Actions

The truth is simple: composite materials are scientifically superior to wood for the mechanical components of a piano action. This is not a marketing claim — it is a fact demonstrated by physics, chemistry, and decades of real-world performance. Kawai was the first piano maker to recognize this truth and act on it, investing millions of dollars over five decades to bring composite action technology to pianists worldwide.

Today, Kawai pianos with ABS and ABS-Carbon actions are played by students, professionals, and competition winners on every continent. The evidence is in the playing.

Experience the Millennium III Action

Discover what decades of composite action research feel like under your hands. Visit an authorized Kawai dealer near you.

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