The time is six o'clock, two hours before the legendary pianist takes the stage to perform.The hall is empty, and still, except for a figure on stage leaning over the piano. This unseen artist is part of every legendary piano performance.
The concert piano technician is a highly skilled craftsman who has dedicated years of training and practice to hone his skills, and just like the famous pianists they work with, they are the very best at what they do. Preparing the concert piano involves tuning, voicing, regulation, and repairs, but only after careful evaluation of the piano, the pianist's needs, and the repertoire for a given performance.
Tonight's unseen artist starts his performance by playing a series of scales and arpeggios. His head is cocked while he listens intently. As he plays he feels the piano's touch, the way the keys respond to subtle changes in velocity and pressure, and makes a mental note of this piano's unique strengths and weaknesses. A quick look at the evening's program reveals that the piano will need to perform equally well for Chopin's subtle, rich, and melodious works, and Prokofiev's loud and percussive compositions. He also checks a hand written note left by the pianist, who has two concerns: a sluggish key, and a section that is too bright.
His initial evaluation complete, the technician starts his tuning procedure. He depresses the sustain pedal, lifting the dampers off the strings and out of harm's way, and carefully inserts a felt strip between the unisons, which are groups of strings tuned to the same note. He does this to mute all but one string for each note. He then carefully measures the pitch of several A notes with his laptop computer. There are as many approaches to tuning pianos as playing them. This technician uses a combination of aural and visual techniques to tune pianos. The computer, equipped with highly specialized software, not only measures the pitch, but also measures the piano's inharmonicity, a unique quality in pianos that requires that each one be tuned slightly different. Using the technician's input, and the inharmonicity measurements, the computer calculates a theoretically ideal tuning for this instrument. The technician next adjusts the tension of one string for each note with his tuning lever, while listening to the pitch, and also watching the visual target displayed on the laptop's screen. Next he listens to combinations of the previously tuned notes, and makes several subtle adjustments by ear. Having satisfied himself that the relationships between the notes, or intervals, is optimal for the evening's performance, he shuts down his computer and moves on to tuning unisons.
The technician tunes the unisons by ear, removing the mutes, and then matching the previously muted strings to those he has already tuned. As he matches each string for maximum clarity he gives the key a sharp hard blow to test that the tuning will hold its pitch, even under intense performance conditions.
The technician now checks the sluggish key noted by the pianist. Sluggish or sticky keys are caused by problems in the piano's action, the complex mechanism connecting the keys to the hammers, which strike the strings. The technician discovers the culprit is a tight hammer flange center pin. He carefully refits the small, felt bushed hole, so that the polished steel pin pivots freely as the hammer assembly swings to meet the string, and then returns to its rest position. He also finds and corrects several other tight flanges. While not observed by the pianist in practice, they could have caused serious trouble during the concert. Using small tools, reminiscent of those used by a dentist, the technician adjusts spring tension and levels the height of the hammers. These adjustments, known as action regulation, will ensure that the action feels even and responsive to the pianist.
Once the technician is satisfied that the tuning and touch of the piano are optimized, he concentrates his efforts on the piano's tone. Not to be confused with the pitch, which is a function of tuning, tone is a function of voicing, the adjusting of brilliance, attack, and sustain. While this piano, a Steinway model D concert grand, has a beautiful tone, the pianist noticed a bright section that was hard to control during his rehearsal. The technician diagnoses that the affected hammers are too hard. He carefully slides the action and keys out of the piano and into his lap. Using his voicing tool, he skillfully jabs the hammers with its needles, needling the hammers of the effected section in the shoulders, near the top, to mellow their tone, blending the bright notes in with the others. He works carefully, too much needling, or accidentally needling the very top of the hammer, could ruin them. He replaces the action and plays through several scales and arpeggios while listening intently for consistency in tone. He repeats the needling procedure until each note strikes with the same intensity and voice.
While not an accomplished pianist, the technician plays the piano. He plays both fortissimo (loud), and pianissimo (soft), using all three pedals as he plays, and listening intently, straining to hear and feel everything the pianist will experience later. His goal is for the instrument to be completely transparent to the pianist. The piano should feel and sound like an extension of the pianist himself.
The pianist performs beautifully that evening. The audience calls him back to the stage with standing ovations for two encores. The technician waits nervously backstage. His audience is not only those seated in the hall, but also the pianist himself. The artist seen walks backstage and seeks out the unseen artist, and shaking his hand he says, "thank you my friend, your work has made this piano a joy to play tonight". In his mind the unseen artist takes a bow, he thanks his Maker for the skills, and then he says out loud, "thank you maestro, it was a joy to hear you play it so well tonight".
Successful concert piano preparation involves a combination of highly developed skills. Piano evaluation, tuning, regulation, and troubleshooting, as well as good communication skills, are essential parts of preparing a piano for an important performance.