Very popular was the ‘London Bach’, his combination of stile galant and Italian forms zestfully received. Four years after arriving in 1762 he produced the Op 5 Sonatas for the Pianoforte (fortepiano? square piano?) or Harpsichord. But Bach, ‘who observed the law of contrast as a principle’ (Charles Burney), even extending the Alberti bass pattern to the treble, probably preferred the newer instrument.

Bart van Oort doesn’t make much of its inherent possibilities in the first four sonatas. Dynamics, always forte or piano with a single crescendo (in the Tempo di minuetto of No 1), are played down – notably so in the second movement of No 3, a theme and variations marked Allegretto. Van Oort glosses over the
very rapid swings from loud to soft in the second part of the theme and at his chosen tempo garbles the semiquaver triplets in Vars 3 and 4. Repeats aren’t always logical either.

Paradoxically, van Oort is comfortable with the absence of any dynamics in the last two sonatas. And options are artistically chosen, scintillating rather than aggressively inflexible in the opening Allegro assai and closing Prestissimo of No 5, the moderator used in the Adagio to enhance an expressively undulating line, an invitation for a cadenza at the third fermata accepted. Shades of Empfindsamkeit probably inherited from CPE Bach are heard too, markedly so in No 6, the most substantial of the set (all three movements are in C minor, a striking fugue in the middle preceded by another invited cadenza) and eliciting the finest interpretation.