Interpretation? Some musicians have little patience for this word, while on the other side there is a recent surge of musicologists who strive to do it justice by elucidating its essence, its development, and its historical peculiarities. After a lengthy period of purely structural reasoning about musical works, topics such as psychology, character, and atmosphere are being considered again. Every tiny portamento or cercar la nota throughout the history of bel canto is being unearthed. Recapitulations are scrutinized with the help of the stopwatch in order to find out whether, why, and by how much they may exceed the scope of the exposition. The anti-interpreters consider all this to be a waste of time. All they ask for is a reliable edition of the score. The rest will be provided by their own genius. Here I would like to interpose and remind the reader of the fact that to decipher a score precisely and sympathetically is a much more demanding task than most musicians realize, and a more important one as well. Among the composers who had the skill to put on paper distinctly what they imagined, Beethoven is an outstanding example. Do not register his markings with one eye only: it will not provide you with the full picture. I am thinking of his dynamic indications in particular — Beethoven was well aware of where his crescendi and diminuendi should start or end. The metronome markings are another matter. The unhesitating adherence to Beethoven’s metronome figures even in the most dubious cases (Op. 106, Ninth Symphony) has resulted in performances that hardly leave any space for warmth, dolce, cantabile, for — in the words of the prescription in his Missa Solemnis — “from the heart — may it reach out to the heart” (von Herzen — möge es wieder zu Herzen gehen). They also leave no room for Beethoven’s humor. While, in the past, it was the cliché of Beethoven the hero and the titan that was harmful to an appreciation of the variety of his music, the danger now comes from the predilection for breakneck speeds and virtuoso feats. Tempi are forced on the music instead of derived from it. My own experience has taught me to trust Beethoven’s markings — if not the metronome indications — almost completely, and to consider them important hints about tempo and atmosphere. The terms from largo to prestissimo that Beethoven uses to indicate tempo and character seem to me frequently more suggestive than metronome prescriptions. Listening to some contemporary performances, the majority of allegros sound to me like presto possibile. The diversity of the tempi gets lost. The third movement of the Hammerklavier Sonata, called Adagio sostenuto, turns into an andante con moto. While the speed of the fugue (crotchet = 144) is technically feasible, it prevents the listener from taking in the harmonic proceedings. (For many pianists, playing too fast may come easier than slightly reining in the tempo.) Another bone of contention is the metronome’s unshakeable steadiness. There are musicians who do not permit themselves or their pupils to use a metronome because it purportedly contradicts the natural flexibility of feeling. Obviously music should breathe, and it presupposes, not unlike our spine and pulse, a certain amount of elasticity. Yet this does not hold true for all music: not only jazz and pop, but also a considerable part of twentieth century music, would, without a rigorous tempo, be senseless. And there is another beneficial function of the metronome: it prevents progressive speeding up. Many young musicians are unaware of what they are doing to the tempo while practicing, and there are virtuosi who consider it their privilege to accelerate the pace while playing fast notes — a habit no orchestra or chamber ensemble could get away with. I cannot acquiesce in the widespread assumption that a soloist may indulge in all conceivable liberties, even the most outlandish ones, because he or she is neither a member of an ensemble nor the helpless prisoner of an orchestra. Quite a few soloists seem to adhere to the belief that only soloistic independence will issue in true music-making that emanates from their innermost interior, unfettered by the strait-jacket of ensemble playing. Any pianist who is about to play a Beethoven sonata should listen to a good performance of a Beethoven quartet — by, say, the Busch Quartet — in advance. And there is more to learn from the best conductors, singers, and orchestras than from all-too-soloistic soloists. Do you know the story of the eminent pianist who early on in his career was accused by a critic of playing semiquavers as if counting peas — with the result that, from then on, rhythmic steadfastness evaporated from his playing? Many years of appearing with orchestras and dealing with string quartets have confirmed my ideal of a rhythmic control that, in solo music, should never stray too far from ensemble playing. After all, the greatest piano composers — excepting Chopin and, in their young years, Schumann and Liszt — have all been ensemble composers as well, if not primarily. It seems highly unlikely that a composer should harbor two distinctly different concepts of rhythm and tempo, one for soloists, another for ensemble players. “Freedom” of playing should be confined to cadenzas, recitatives, and sections of an improvisatory nature. It goes without saying that Beethoven’s scores are neither entirely complete nor apt to be put into practice by a computer. To prepare the onset of a new idea, to give sufficient time to a transition, to underline the weight of an ending: these were self-evident matters that the performance of tonal music implied. 
Compared to the younger and short-lived Schubert, Beethoven had more time and opportunity to hear his own works performed, and to react to the performances. His hearing trouble was probably not so severe that it would have prevented him from perceiving certain tones and nuances. The Schuppanzigh Quartet, an institution that had already been associated with Haydn, accompanied his string quartet production
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