Category Archives: piano video

Music : David Stanwood: A passion for piano

By Karla Araujo
Photos by Ralph Stewart

Published: November 12, 2009
Martha’s Vineyard Times

David Stanwood knows his way around the inside of a piano the way a Grand Prix mechanic knows every nuance of his Formula 1 race car.

It’s this knowledge – combined with curiosity, persistence, mechanical aptitude and an appreciation for the rigors of math and science – that has earned this West Tisbury resident an international reputation as a piano innovator.
West Tisbury resident David Stanwood, inventor of Precision TouchDesign, with his latest invention, Stanwood Adjustable Leverage Action.
Which allows the player to alter the feel of the keys, creating the perfect balance between musician and instrument.
When he was studying piano tuning and repair at the prestigious North Bennet Street School in Boston, he asked his instructor how to change the feel or action of a piano.

“The teacher, who seemed to know everything about pianos, had no clear answer,”  Mr. Stanwood says, still sounding mildly incredulous 30 years later.

What made one piano so effortless to play and another so difficult?

And why did the feel of even the same model piano by the same manufacturer vary from one to the next?

His dream: to create a system of metrology, a science of weights and measures, to explain how to balance piano action.

He discovered that playing a piano was like riding a bicycle: a piano that offered a consistent touch allows the player to move smoothly and effortlessly through the music, just as a paved road offers the cyclist an easy glide.

In contrast, a keyboard that feels inconsistent from note to note acts as a barrier between the music and the musician, the way a potholed road forces a rider to watch for hazards rather than just relaxing and enjoying the journey.
Mr. Stanwood’s work requires a steady hand and a meticulous approach.
To solve the riddle of piano action inconsistency, Mr. Stanwood began the arduous task of removing each piano’s components to weigh and measure them.

He devised a system that took apart the action and analyzed the measurements, allowing him to understand the relationships that, as he puts it, “revealed themselves as an algebraic expression, ‘the equation of balance’ – a fundamental algorithm that explains the weight leverage characteristics of piano action.”

His company, Stanwood Piano Innovation, applied this approach to the reconditioning of pianos around the world through a network of technicians trained in Precision TouchDesign.

This patented approach can reconfigure the touch of any piano to achieve a degree of feel and tone that he characterizes as higher than any attained previously.

A piano is an intricate piece of artistry that allows the musician to interpret many types of music in many different ways. It contains more than 200 strings and upwards of 10,000 individual parts.

Most pianos have 88 keys, the depression of which causes a hammer to strike one, two or three strings. Simply put, these different parts work in unison to comprise the “action” of the piano.

Computer technology enabled Mr. Stanwood to track measurements from piano to piano. By developing new standards of measurement, he could create more predictable feel and response from each instrument.

With accolades from the late piano virtuoso Rudolf Serkin and jazz icons Keith Jarrett and Chick Corea, and “Stanwood-ized” pianos commissioned by such institutions as the New England Conservatory, the Boston Symphony Orchestra and Brandeis University, David Stanwood’s pioneering work is slowly gaining acceptance.

His Precision TouchDesign is part of the curriculum at North Bennet Street School and at Florida State, the only university in the U.S. that offers a masters degree in piano technology.

“I chose a very conservative field,” Mr. Stanwood explains, with cheerful resignation. “It’s tradition-bound. If you attempt change, it’s sacrilege. It takes time to overcome.”

He traces his desire to question authority to his childhood in the 1960s. “I found that it worked to open doors. And it helped me to discover a whole body of knowledge that benefits our culture.”

By altering the touch design, Mr. Stanwood can customize the action of a piano to suit its owner – from light to heavy, depending on the physique and health of the player.

Many of his customers are what he calls “passionate amateurs,” avid players whose pianos may not suit their style of play and who are willing to pay an average or $2,500 to have their piano reconditioned.

“By practicing countless hours every day, concert pianists learn to adapt to different pianos,” he says. “Amateurs are really my best customers – they need more help than the professional.”

And, while Stanwood Precision TouchDesign enabled Keith Jarrett to resume playing following a crippling bout of chronic fatigue syndrome, the system’s only limitation was that once a piano was modified it was not adjustable.

Until now.

Never content to accept the status quo, Mr. Stanwood envisioned creating a system that could adapt not only to the musician but to the type of music being played as well.

Today he is in the process of yet another breakthrough in piano technology: the Stanwood Adjustable Leverage Action, or SALA. With the twist of a knob, the player can change the feel of the piano from heavy to moderate to light, striking the perfect balance between person and instrument.

With SALA, a single piano can suit players of different stature or physical condition. And the pianist can better match the feel of the piano to the musical selection.

David Stanwood is on his way to achieving his dream: to make the mechanics of the piano disappear from the player’s mind.

He says, “I get incredible joy from helping musicians to create better music.”

Karla Araujo is a regular contributor to The Martha’s Vineyard Times.

metropolitan museum: curator emeritus of the musical instrument collection


“Piano history isn’t over. You’re writing a new chapter. Thanks! ~ Laurence Libin”

Musical Instrument Collection

Laurence Libin, Curator Emeritus of the Musical Instrument Collection, Metropolitan Museum, NYC – after playing the first production prototype Stanwood Adjustable Leverage Action by David Stanwood, April 2009

WGBH piano video shows mathematics in service of world culture

This video was created by WGBH Public Television Boston for the Annenberg Network series on Mathematics as an example of someone who has put Algebra to use in the real world in service of world culture.


There are three additions I’d like to make:


When using 1 gram blocks simulating the piano hammer out on the far end of a see saw,  the movie shows me placing the block on the table instead of on the end of the beam.

The reason, which is not shown,  is that I place weights along the beam to simulate all the parts of the key.  When they are in place then I place the 10gram weight on the end of the seesaw and slide it along until this beam is balanced.

How far out the weight is on the beams tells the weight ratio of the action.

Finding the position for a known weight on a see saw so that the see saw balances level is an analogy for solving an equation for a single unknown variable.


When displaying the hammer weight analysis of a Hamburg Steinway D in Jordan Hall, New England Conservatory of Music. The data shows a big dip in the weight.

This is the way it came from factory and it’s usually the hammer weights are found to be smoother in these pianos but you never know until you measure them..

What the video does not say is that the dashed lined on the graph just above the hammer weights is the new Precision Touch Design specification after  modifying and upgrading this action.

Lead weights were inserted into the wooden portion of the piano hammer to bring the weights up so specification.

The result is a more even and predictable result in the response of the keys and more evenness in the tone.   Bringing the weight level up also increases the projection of the sound and fullness of the tone which is important in a concert hall.


After showing a graph of how much lead weight is in the keystick from the factory and how the equation is used to smooth out the weight inconsistencies, I mention that we use a wippen support spring added to the existing parts.

A combination of spring tension and lead weight is used to create a faster, quicker action without giving up hammer weight and tone.

It should be noted that we do not do this to all Stanwood Action jobs.  It is what we call a “High Performance Option”.

Fazioli: invention makes playing a superb piano even more enjoyable

fazioli F228


That was my first reaction after the Stanwood Precision Touch Design was installed.

Suddenly I was able to play passages that had always eluded me, or demanding pieces like the Chopin etudes that previously I could only stumble through.

In the past I assumed the problem was with me. What a revelation to discover that I had much greater potential as an amateur pianist than I ever imagined – as long as the piano was performing at its top capability.

David Stanwood selects his technicians carefully and trains them well.

My technician wanted to understand completely what I was looking for in a piano action, and exactly how I played the instrument (did I stroke the keys, or push down more heavily).

Everybody’s style of playing is somewhat different, and one of the great benefits of the Precision Touch Design is that it corresponds to your style of playing. My technician also recommended an enhancement to the Precision Touch Design – adding magnets to the action to improve responsiveness and tonal control.

I was nervous at first about installing the Precision Touch Design. My instrument is an older model Fazioli F228, which is already an exquisite piano.

The Precision Touch Design improvements, however, were immediately discernible and very substantial. They made playing a superb piano even more enjoyable.

Frankly, I wish I had done this a lot earlier. I wasted years blaming myself and my technique, when all along it was the instrument that needed improvement.

I’ll leave you with just one example.

Beethoven’s last movement of his Waldstein sonata has some famous octave glissando passages. I always played these glissandi with two hands, like the editors’ notes suggest “for the modern piano.”

Everybody knows the modern grand piano’s action is too heavy when compared to Beethoven’s instrument. A few months after installing the Precision Touch Design I was playing through the Waldstein sonata and nearly fell off the piano stool when I discovered I could play these octave glissandi as written, with just the right hand.

Somehow David Stanwood has discovered a way to transform the modern grand piano into an instrument capable of performing with all the lightness of an early 19th century instrument, without sacrificing any of the depth of tone.

Now that’s genius!

-Garrett Glass, Chicago Illinois
Client of PTD installer David Graham

piano restoration: invention certainly accounts for our busy shop and backlog

cllahan piano serviceLetter from John Callahan

We are Callahan Piano – one of the few “Left Coast” Stanwood connections.

It was great to have a small group of installers gather recently after the CA State PTG convention. All Stanwood folks have an open invitation to come and visit whenever you find yourselves in the Bay Area.

We are a fair sized shop specializing in high-end piano restoration – 95% Steinway and Mason & Hamlin.

We are pleased and proud to have four licensed installers working together under one roof – and complete an average of two PTD’s per month. We are a bit different in that we restore for clients only – we do not buy and sell.

Licensed Installers since 2001, we made the decision some time ago not to do an action job without PTD – and that certainly accounts for our busy shop and backlog.

The more Stanwood actions we do – the more folks want it.

When a potential client can visit the shop and play one, and sometimes two or three pianos, all with the same mind-blowing ease and evenness – the decision to have us do their action becomes easy.

Our success over the past few years has been the result of fairly intense marketing efforts to get local pianists and potential clients into the shop whenever we have a completed instrument.

We have also found it very effective to host “send-off” parties on completion of a major restoration. The client invites friends and colleagues, and we supply wine and cheese, and the piano is the star of the evening. Lot’s of fun. (And the biggest plus – it gets the shop cleaned up!).

Thanks to David for all his work which has benefited so many technicians and pianists!

Best regards to all,


John Callahan, Callahan Piano Service