There is a priceless BBC Television clip of Jimi Hendrix playing Hey Joe on The Lulu Show in 1969, in which the rock giant audaciously pulls off a typically brilliant solo by retuning his guitar strings, note by note, before turning to his band with a "did you see that" grin spread across his face. Try to imagine being able to do the same thing on a piano - sliding and bending single notes by up to a whole tone to match the emotive blues of the guitar, or the refined, keening elegance of an Indian santoor. With the invention of the Fluid Piano, you don't need to imagine any more - you can try it out yourself.
After more than 10 years in development, and currently the only one of its kind in the world, it is a piano, but not as we know it. For its inventor, its arrival marks the first major change in the instrumental canon since the architecture of the European classical orchestra was set in the 19th century. Unveiled at a private recital at the University of Guildford at the end of November last year, and due to feature in its first major concert at the South Bank Centre in London in March, the Fluid Piano is the brainchild of the Brighton-based dulcimer player Geoff Smith.
Smith is one of the world's leading experts on the hammered dulcimer, which, like the cimbalom, is one of the ancestors of the piano. He also happens to be an acclaimed composer of live soundtracks for silent cinema classics such as The Cabinet of Dr Caligari and Faust. While the modern concert grand piano is a mighty beast with a cast iron plate supporting nearly 40 tonnes of tension from the steel wires, the Fluid Piano is based on the 18th- and early 19th-century fortepiano at which Hadyn, Mozart and Beethoven wrote and performed some of their greatest works. Like the Fluid Piano, these instruments have no iron frame and offer a less dynamic range than later pianos, but have a clearer and more precise tone and lighter action.
The one Fluid Piano in existence is currently housed in a rehearsal room in Guildford University in Surrey. It took almost two years to manufacture and is a splendid looking instrument, fashioned from a light ash (rather than the usual coffin-top lacquers) by Christopher Barlow in Somerset, an instrument maker who specialises in building harpsichords, fortepianos and harps. "We worked very closely and intensely together to make the idea work," Smith says. "A lot of problem-solving had to be done. It took about 16 months to actually build it."
Now that it is here, he argues, we are all about to experience a cultural paradigm shift. "The Fluid Piano challenges and actually changes the definitions of music - of western classical, and world music." The major innovation from forte to Fluid Piano is in the tuning, and the slide mechanism on top of the instrument, in front of the player, which allows musicians to microtonally adjust the tuning of each of its strings, key by key, right there in the heat of a performance, to their own specifications, so that players can bring non-western scales into what has hitherto been a definitively western classical instrument.
For Smith, it opens the lid on a future where performers of all kinds - from Indian, Persian, Arabic, African or Asian traditions, the worlds of jazz, improvisation, classical and blues - will be able to plunder the virtually infinite range of microtonal tunings possible on the instrument. And make music together. One of the instrument's earliest supporters was Pam Chowhan, a classical pianist and violinist and head of planning at the South Bank Centre. The Indian-born Chowhan was part of the line-up of musicians at Guildford that included the jazz pianist Nikki Yeoh and the modernist improviser Matthew Bourne.
"I was astonished that he'd got it made at all," Chowhan says. "Then I went down to see it and when I started playing the first thing I did was tweak some of the notes. As a string player, I sharpen and flatten certain notes for expressive reasons. I started doing that with the piano and thought, 'Well this is brilliant, I can actually play this with the same expressive intonation that I use on the violin.'"
She tried a Romanian dance by Bartòk, and one of Erik Satie's Gymnopédie, and was amazed by the result, and the enhanced freedom of expression and emphasis that microtuning brought to her interpretation of the scores. The Iranian pianist Ramin Zoufonoun has yet to get his hands on the Fluid Piano, but heard a good deal about it directly from Smith himself. Zoufonoun is renowned for playing the conventional piano in a range of Persian tunings, and sees huge potential in the microtonal instrument.
"I'm anxious to see how it feels - the touch, the action, how friendly it is to tune, how it holds the tuning," he says. He hopes to be able to fly over from America to be a part of the South Bank recital in March. What would he want to play first? "I'd like to perform some tight combination of my composed and improvisational works in the Dastgah [modal] system of Iranian traditional music. I would also demonstrate the change of tuning during the performance. This is one key element of the Fluid Piano which would revolutionise the use of piano for Persian classical and any other music that uses scales other than the well-tempered 12-semitone scale."
Indeed, what the invention of the Fluid Piano does is take the piano out of the ring-fencing around the classical western orchestra and sets it down the Silk Road and towards the myriad microtonal worlds of non-western musical forms. For Smith, and performers such as Zoufonoun and Chowhan, it is a revolutionary new approach to the vast musical canon outside the European classical tradition - a canon that can be too easily categorised as "indigenous", "ethnic", or "other".
"It is the first multicultural piano," says Smith, "and it touches on the wider issues of culture and assimilation. Its sheer existence asks a lot of questions, such as why it gets very open, positive reactions to its creative possibilities, as well as negative, prejudiced responses." He points to some of the comments that have appeared with film excerpts of the instrument's premiere in Guildford on YouTube. "It's like a mirror of the player and of the person because of what it encapsulates. If you're prejudiced to the idea, what does that say about you and your attitude to people from other cultures?"
For Smith, music does not exist in a bubble, independent of whatever is happening in society - and nor does the Fluid Piano. "It captures the zeitgeist," he says. "The orchestra, and the instruments of the orchestra, are locked in time, whereas society keeps changing - we live in a multicultural society, and there's a lot of argument about that, and prejudice that people have to deal with each day. And I feel the Fluid Piano is something of a symbol of that, as well as a working instrument."
Chowhan will be among the artists taking part in the instrument's premiere at the South Bank, and she too is fascinated by the potential repertoire opened up by the instrument: "There are so many possibilities for this, because there are so many different, non-western cultures that the Fluid Piano fits into with its different tunings. "I could just see how that sound could fit in to that kind of music. Especially in India, you get a lot of musicians who want to incorporate a keyboard or a piano, and they do it, and it sounds really awful. You have this grating tuning, because they're doing one thing, and the keyboard is rigidly staying in that tuning."
Smith is in negotiations with different instrument makers to manufacture more Fluid Pianos, but for the moment, it remains the world's loneliest instrument, albeit the focus of a documentary feature film by the director Rafael Lewandowski, who will be filming at the South Bank and, later, at the Fluid Piano's next public unveiling at a Chopin festival in Poland. "There's only one piano, which is frustrating," says Smith, "but the sheer fact that it exists means there's been a shift in the balance of power artistically, emotionally and philosophically in what it makes possible, across a whole range of music. It helps you to release your individual culture much more. It gives any artist a wider palette of creative choices from which to draw. You can express yourself more as an individual, and that may be the most exciting thing, in the end."