Some time ago I was reading a book about ancient music and remarked that many keyboard works, written in the days of the clavichord and harpsichord, suggested a tonal power impossible for the now obsolete instruments for which they were written. I [had] in mind the various works of Bach, particularly the Fugue in B flat minor (in the second book of the Forty eight), the substance and power of which seems beyond any clavier known to Bach [1]. Yet that clavier sufficed him: and we are left wondering, not only in this instance, but also in that other Fugue in B major, which in places involuntarily recalls Wagner’s Die Meistersinger overture. This tonal density is, with Mozart’s works, in inverse ratio to that of Bach. The modern grand piano, which is the ideal instrument for the performance of many of Bach’s keyboard works, can only be satisfactory in the performance of Mozart’s works when the technique and interpretation is light-fingered and crisp enough to be Mozartean. To play Mozart with the weight and power required for Bach and Beethoven would misrepresent Mozart and substitute wooden legs for airy limbs.

A minority of composers shy at the full power of the grand piano. In some lectures by Alfred Cortot, recently published, that great artist told the students that it was almost impossible to play certain piano works by Debussy satisfactorily on a concert grand as the composer ‘heard’ them, because the instrument he used was an upright grand with a very light touch. Mozart and Debussy occur to me as similar cases exceptional from the mass of modern composers for the piano: many modern piano works appear to be suitable for a piano of six times the tonal density of an ordinary grand. 

A piano such as Chopin preferred — the old Broadwood square boudoir piano of two strings and wooden frame — would seem an ideal piano for Mozart and Debussy. Those of us who first heard the works of Chopin on a modern concert grand, and have continued to hear them so played, have recently been reminded that this modern tonal density is out of all proportion to that used by Chopin the composer. Yet it seems impossible for us to believe that the full-blooded substance of the B flat Waltz, the Fantasy in F minor, the A flat and B major Polonaises, or the Studies could ever be transmitted on a bichord piano: that such works were interpreted in the subdued tone power practised by Chopin.

James Huneker, who never saw Chopin or heard him play, wrote a wonderfully inspiring book about the man and his music. Refined spiritual ecstasy such as flows abundantly through all Chopin’s wonderful dances is not met elsewhere to the same extent. Yet, wonderful as it all is, there was one famous musician, Busoni, who intended quietly to protest against Chopin’s Nocturnes. But a year or two before his death he had reactions. He contemplated a series of recitals and to revive Mendelssohn’s Songs without words (their neglect is unjustifiable) and Field’s Nocturnes, his reason being that the latter’s original nocturne was purer in type than any by Chopin, whose ingredients had been baneful to the beauty of the original [2]. 

Busoni was near to death: but it is curious that his sensitive mind should have reacted in favour of Field. It was always so; the new thrusting aside the old. Thomas Mace almost wept when he saw the modernity of his day sweeping away the long-established family of viols. His protests availed nothing. About the time Chopin was playing on a bichord piano, Wagner at Zürich was conducting an orchestra ‘greatly augmented’ to sixty (!) players. We have moved far from the days of the proportion of from 25 to 40 players for a Mozart symphony, or a similar orchestra of 60 for Beethoven or Brahms. Such things are now rare. Our ears have grown accustomed to a power and tonal density undreamt of in the forties, and a reversion to the conditions of that period would sound as thin and colourless to us as if we attempted Bach’s Forty-eight Preludes and Fugues on a clavichord.

On the other hand, by La main gauche, Musical opinion, July 1937, pp864-865

(1) See EJ Dent's Busoni biography for Busoni's attitudes to Chopin – he revered the Preludes but discounted the Nocturnes as representative of the 'feminine' side of Chopin that he disliked, and always played Chopin in recitals in a strong, 'masculine' manner.

(2) This fugue appears to have been HB’s favourite of the whole 48, and he occasionally cited it as a parallel to, if not an influence on, his own Symphony No 8, which is in the same key.