Sound and Vision: the genius of Henry Dagg

The Sharpsichord, invented and fabricated by Henry Dagg

The Sharpsichord, invented and fabricated by Henry Dagg

The Sharpsichord

This ten-foot tall, two-and-a-half ton monster, fabricated out of solid stainless steel, is a mechanical musical instrument called the Sharpsichord. It is the creation of Henry Dagg, musician, artist, engineer, and visionary inventor. Originally conceived as a commission for the English Folk Dance and Song Society at Cecil Sharp House, the project overshot the  specified timescale of six months by five years, and the allocated budget by many thousands of pounds. The realization of the brief simply outgrew the commission, and assumed a majesty above and beyond today’s corporate vision of patronage.

Dagg 4The instrument/sculpture was finally completed by 2011,  and in that year it was incorporated into the touring production of Bjork’s  Biophilia (the video I have linked is introduced by Sir David Attenborough, which makes it even more delightful to watch).

I recently visited Henry Dagg at Biscuit House, his workshop in Kent, where I was able to examine the beautiful workings of the beast and hear it sing, and to discover more about Dagg’s extraordinarily intense creative process.

Design and Concept

The instrument is named after Cecil Sharp, a nineteenth century musicologist who collected and classified traditions of English folk music. Sharp made pioneering recordings of songs on the early phonograph, which is referenced in the Sharpsichord’s two great acoustic horns. They amplify in stereo the music made by the array of strings at the back – the larger one for the bass notes, and the smaller for the treble. The music itself is programmed manually on the large pin-barrel that dominates the front of the structure. As it rotates the pin-barrel activates the mechanisms that pluck the strings of the harp at the back. The instrument can be hand-powered by means of a crank-handle, or by a motor running on stored energy from the solar panels at the top. There is  a small keyboard to help the programmer with note-finding on the pin-barrel. The keyboard also operates the mechanisms that pluck the strings and can be played – if you have fingers powerful enough to exert the force required.

The Music

The sound or “voice” of the Sharpsichord is quite unique – sort of harp-like, but metallic and with more attack, well amplified thanks to the steel horns. There is an underlying susurration like the whisperings of a mechanical throat. In a strange way the whisperings animate the sound, like the breath of a sentient being. You can hear the instrument in the video clip below, filmed in the workshop where it lives.

Dagg 5

The Sharpsichord’s array of mechanical plectra and dampeners that are activated by the pins on the barrel.

The array of levers and jacks that operate the Delrin plectra at the back – one set for each of the 46 strings – are painstakingly engineered, as are their corresponding dampers (those are the levers at the front of the picture above). The strings are made of stainless steel wire, their gauge carefully graded to the correct pitch,  kept in tension by counterweights so they never need tuning. All this represents months or even years of experimentation and making prototypes for each part. As Dagg said, the detailed research and development that goes into a project such as this represents a vast proportion of the time given over to the realization of the sculpture.


This is where I am somewhat in awe of Dagg’s technical skills as an engineer, because he works intuitively, developing components of the instrument as it progresses. Apart from conceptual drawings for the overall visualization of the project, he does not appear to make any technical drawings, which means that the work cannot be delegated to a firm of engineers. He carries it all in his head and works things out in the shop, which implies a total immersion in the work, day after day, for the years it takes to complete.

Hand-fabricated cranks and gears

Hand-fabricated cranks and gears

Henry Dagg’s choice of stainless steel for the fabrication of the Sharpsichord was a practical response to the original brief, that required the sculpture to be installed outside in the gardens. Stainless steel is very hard-wearing, not prone to degrade in the way that mild steel would. Being very hard, it is great for precision engineering, which was essential for making the complex mechanisms of the harp. But it is a very expensive metal, and it requires advanced metalworking skills for its fabrication. As Dagg remarked, “It’s entirely fabricated by bending flat bar into curves, followed by an infinity of cutting, welding, grinding, and polishing. The transmission called for a lot of lathe and other engineering work.”

Dagg 7

Henry Dagg’s Dean Smith & Grace type 21 lathe – you can see the Sharpsichord in the background.

Engineering Shop

Henry Dagg lives with his fabricating machines. They are beautiful. Perfect in form and function – their form governed entirely by the function for which they were designed. We discussed this concept in relation to aesthetics, which is integrated into the way he conceives his pieces. Whatever is required for the realization of the instrument – be it a tiny and precisely machined component, or a very large and slick piece of construction, there is a machine that can handle the job, and Dagg will go out of his way to acquire it. To date, he has about ten different lathes and several milling-machines and drill-presses, in addition to the usual shop equipment for welding and fabricating. It is a very exciting place to be for anybody who has an interest in making things, because the sheer variety of processes available expands creative horizons and makes ambitious ideas possible to realize.

Dagg 8

Detail of the DSG Type 21

The machines date mostly from that period of solid British engineering in the 1950s and 60s. Each one is lovingly maintained, each one almost alive with its own little idiosyncracies. I am not an engineer, but I cannot help but get excited by these heavy-duty engines, warming to the sounds of their motors as one would savour the roar of an elite sports car or motorbike!

Art and Patronage

It was these machines that birthed the Sharpsichord, and they have been busy over the last few years on Henry Dagg’s current project, a monumental set of gates that can be played like a cathedral organ for Rochester Independent College, due to be installed later this year.

As a deeply committed artist myself, I feel inspired and vindicated by Dagg’s uncompromizing dedication to realizing these extraordinary projects. Achieving great work is a journey. A project develops from the accumulated experience of the artist, but then takes on its own character, carrying its creator on its trajectory. And the production of great work requires inspired patronage, supporting the journey, rather than merely laying claim to outcomes hedged in by policy, unrealistic timescales and meagre budgets.