A New Voice for Boston Grand Pianos: The Steinway Hammer

In the ongoing evolution of piano design, Steinway & Sons continues to invest deeply in innovation—extending its expertise to every instrument in the Steinway Family of Pianos.

The newest advancement comes to the Boston grand piano, featuring a completely redesigned hammer crafted in partnership with the Renner piano action company.

Designed by Steinway. Built for Boston.

Because Steinway owns the Louis Renner company, the design team could pursue an ambitious goal:

Create a hammer for Boston that delivers exceptional clarity, tonal projection, and consistency—while preserving the warm, balanced voice Boston pianists love.

This long-term collaboration has produced a remarkable result: a hammer designed, engineered, and made by Steinway & Sons, marked by the Steinway lyre on every molding.

About the Steinway / Renner Collaboration

For more than 135 years, the Louis Renner Piano Action Company has been a benchmark of excellence in piano mechanics. Based in Stuttgart, Germany, Renner has supplied precision-crafted actions and hammers to nearly every leading European piano maker, including Steinway Hamburg, Bösendorfer, and Bechstein. Renner’s reputation is built on meticulous tolerances, hand-selected materials, and unwavering quality, making it a natural partner in Steinway’s ongoing pursuit of refinement.

When Steinway acquired the company in 2019, their CEO remarked:

“We wanted to ensure that Renner remains in Germany, where they have been for nearly 140 years, and that they continue to deliver the world-class quality they have maintained throughout their history. Renner produces essential components for our Steinways, which makes this continuity vital to our company.”

Inside the Innovation

1. Weickert “Special” Felt
   The new hammer features Weickert “Special” felt, the same premium material used in Hamburg Steinway hammers. Known for its voicing stability and resilience, this felt maintains tonal integrity and control over years of performance.
2. Signature Purple Underfelt
   Each hammer includes Steinway’s signature purple underfelt—a dense, high-end layer used only in the company’s finest instruments. It enhances longevity and ensures tonal consistency across the dynamic range.
3. Hornbeam Moldings
   The hammer moldings are made of hornbeam, a hardwood with excellent strength and dimensional stability.  Hornbeam’s properties make it an ideal match for Boston’s design philosophy, optimizing energy transfer and tonal clarity.
4. Refined Shape and Compression Profile
   Steinway’s engineers developed a new kettle shape and compression ratio, creating a hammer that is slightly firmer than a New York Steinway hammer and tonally closer to the Hamburg hammer, yet with a distinct Boston identity.

Two Hammer Sizes. One Unified Standard.

The new hammer comes in two size groups, each carefully scaled for the instruments it serves:

• Group 1: Boston GP-156, GP-163, and GP-178
  
  
• Group 2: Boston GP-193 and GP-215

Each hammer set is voiced and balanced to the specific scale design of its model group, ensuring optimal tonal projection, uniform response, and a seamless playing experience across the Boston grand line.

This advancement will also extend to Boston upright pianos later this year, and potentially to Essex models in the future—bringing the same tonal clarity and consistency across the Steinway family.

The Result: Clearer, Richer, and More Expressive

Technicians and artists alike describe the results in simple terms:

“Better harmonics.” “Richer.” “Improved.”

The sound is more focused, with enhanced projection, greater harmonic depth, and the unmistakable Steinway hallmark of clarity with color.

Continuing the Steinway Tradition of Improvement

Every piano in the Steinway family embodies the company’s spirit of continual refinement. The new Boston hammer reflects that philosophy—melding Steinway’s renowned craftsmanship with modern engineering to produce a piano that inspires players at every level.

Experience the next generation of Boston tone.

Schedule a private demonstration or visit M. Steinert & Sons to hear how the new Steinway-designed hammer brings new color, clarity, and balance to the Boston grand piano.