Perhaps the single most important person in the highly strung world of classical music, the master tuner Ulrich Gerhartz knows all there is to know about the piano, writes Jasper Rees. It's amazingly easy to disembowel a grand piano. With little more than a flick of two wrists, the blocks are removed from either end of the keyboard and the entire internal mechanism comes away. I am onstage with Ulrich Gerhartz, a wiry man in a trim blue apron in whose lap the keyboard now rests. The hundreds of seats out in the concert hall are unoccupied. Around us are three pianos, each a Dh534,000 Steinway concert grand model D with its lid up. Gerhartz is possibly the single most important figure in the entire piano world. Stored in his mobile phone he has the number of just about every top pianist on the planet. When Alfred Brendel made on his farewell tour, Gerhartz came too. When Lang Lang lands in London and needs his Steinway set up for maximum impact, who's he going to call? But back to the innards. With one hand, Gerhartz has isolated a particular hammer from the other 87 serried either side. With the other he is painting a clear liquid on to the hammer's green felt coating. "There was one note here, an F sharp, that wasn't bright enough," he explains. "So I used a mixture of collodion and ether to bring the hammer note out a bit. You apply it right on the nose of the hammer and it stretches the felt, so it makes it slightly harder and gives the note a bit more attack and brightness." From his array of little instruments, Gerhartz chooses what looks like a hypodermic dart, and starts pricking the felt of the F sharp hammer nose. "Having made it brighter you don't want it dull again. That makes the felt softer." Steinway's director of concert and artists services is a master piano tuner. Maybe even a maestro. There's nothing he doesn't know about Steinways, which are the top pianos in the world, including the Middle East. "The Middle East is certainly a growth market unless everything goes belly up" he says. One of Steinway's key clients is the Sultan of Oman, though his resident team of piano tuners are trained in London and Steinway's European HQ, Hamburg. Are there problems with keeping the pianos in tune in the hotter climates? "In the past, in the damp sub tropical climates pianos were made to last a bit more. But if it's really bad, the piano is going to suffer. Now with climate-controlled halls it's much easier. As long as pianos are in an air-conditioned environment all the time, they are fine. The worst is to have a venue that is not air-conditioned when it's not used and then they turn it on full welly." Even in temperate climates, tuning is not always simple. American orchestras tune to a pitch of 440 Hz, while European ensembles generally go for 441. There is one horror story - before Gerhartz's time, he insists - when the Russian pianist Mikhail Rudy requested a last-minute change of Steinway at the Royal Albert Hall in London. Somehow no one noticed that the piano was pitched at 440 while the orchestra played at 444. "It was awful. It made the newspapers." In preparing a concert grand for performance, there's a bit more to the job than pitching. Every note has to pull its weight, every hammer, every string, every key, which is why when he gets under the bonnet of a piano he might not come up for air for an hour and a half. There is regulating, voicing, balancing between bass and treble to do. His fingers trickle neurotically up and down the keyboard playing chromatic scales. Anyone else would be doing this to hone technique. Gerhartz is hunting for bum notes. When he finds something, in an area an octave above middle C, he takes a stick of chalk in a smart gilt holder and deftly marks the wood above that offending F sharp. Without wishing to go in for national stereotyping, there is a Teutonic reliability about Gerhartz that may help account for his pre-eminence. He seems extremely meticulous as, for the umpteen thousandth time, he picks up a short stick and starts taking measurements from strings inside the piano. "It's a blow gauge," he explains. "You hold it down from the string to the hammer and you can see what distance the hammer is from the string. The hammer has a certain distance to accelerate before it hits the string. And that has a very big impact on the depth of touch - how far you push the key down in order to get the hammer to the string." Depth of touch is all-important. Some pianists like the piano to be set up so that all they have to do is tickle the key and a note sounds. Others opt for resistance. Preference is not necessarily gender-specific. Gerhartz sometimes gets pianists asking him to set up the piano just as the legendary Vladimir Horowitz preferred it in the belief that it'll make them sound like him. "Horowitz made an amazing sound with a very, very light shallow keyboard with a very, very, very bright tone. But if you gave a piano like that to Alfred Brendel it would be unplayable for him. Unthinkable." He never has problems with the great pianists. If anything in the highly strung world of solo performance tries his patience, it's the youngsters. "A lot of them grow up in such a bubble of how wonderful they are and they just think, 'A piano tuner is trade and I'm too good for them'. Pianists who don't talk to me won't get any service because I don't know what they want." As he prepares their Steinways for performance in an empty concert hall, do his fingers never ache to strike up a sonata? "Not really, no," he says sheepishly. "That's not my job. I can play a bit, yes. But I'm not a pianist by any means." And he gets back to the everlasting hunt for bum notes.
