The first decade of the twenty-first century has seen the steady emergence of discs featuring compositions by Johann Nepomuk Hummel (1778–1837): we now have access to seven of the eight extant solo piano concertos and to much of the chamber music, and anyone interested in Hummel's solo sonatas has an increasing variety of interpretations to explore. The dearth of scholarly editions persists, but we do now have a full-scale biography of Hummel in English, Mark Kroll's Johann Nepomuk Hummel: A Musician's Life and World (Plymouth: Scarecrow, 2007). Madoka Inui's Hummel at the Opera ventures into the shadowy realm of Hummel's ballets, operas and pantomimes, interlarding Hummel's solo piano arrangements of excerpts from originally orchestral scores with several sets of variations on borrowed themes. The arrangements include the Quintuor des nègres from the ballet Paul et Virginie and the Potpourri No. 1 from Hummel's opera Die Eselshaut, or The Donkey Skin, based on a somewhat arcane folk-tale about a king's daughter who, on the advice of a fairy, circumvents her father's desire to marry her in place of his dead wife by demanding the slaughter of the Golden Ass, in whose skin she eventually flees. This is Inui's second disc devoted wholly to compositions by Hummel. The other, which will serve as a periodic source of comparison in this review, was her 2005 release Johann Nepomuk Hummel: Fantasies (Naxos 8.557836A). This included the world premiere recording of the Fantasie in G minor on themes of Neukomm and Hummel, Op. 123, the more familiar Fantasie in E flat major, Op. 18, and the intriguing Fantasie ‘Recollections of Paganini’.

In pursuing a multidimensional career of composing, performing, teaching and administration, Hummel was typical of his time. Whereas the solo keyboard output of earlier figures such as Muzio Clementi (1752–1832) and Jan Ladislav Dussek (1760–1812) generally affiliates certain conventions with certain genres, Hummel's works often amalgamate procedures associated with, say, the large-scale professional solo sonata and those connected with the reputedly more meretricious genres of operatic variations and fantasias. Conversely, the techniques emanating from Hummel's celebrated prowess as a virtuoso performer and improviser as manifested in the fantasias and variations (such as quotation followed by ‘improvisatory’ elaboration) frequently spill over into other compositions ostensibly uninhabited by the spirit of quotation and improvisation: Hummel drew on Cherubini's Les deux journées not only in the variations included in the present disc, but also (as the liner notes mention) in his Trumpet Concerto of 1803. He has great fun with motives from the finale of Mozart's ‘Jupiter’ Symphony in the third movement of his otherwise earnest Piano Sonata in F minor Op. 20. In the sonata finale the approach resembles the free admixture of themes from the outer movements of Paganini's Violin Concerto No. 1, Op. 6, in the Recollections of Paganini included on Inui's 2005 disc.

Turning to the later recording, compositional sophistication inheres in some of the variation sets’ engagement with distant keys: the set on ‘Vivat Bacchus’ from Mozart's Die Entführung aus dem Serail, Op. 34 No. 3, in C major, turns in its ninth variation to A flat major, the key of the flattened submediant, before eventually invoking E/F flat major, the flattened submediant of the flattened submediant. Another third-related shift permeates the final variation of Armide, and it is presumably to this that the liner notes refer with their observation of ‘an anticipated Schubertian passage in Variation 9’ (actually Variation 10). These examples more directly recall the similarly ‘improvisatory’ harmonic moves in the extended codas of several of Beethoven's nine variation sets published between 1795 and 1800. Perhaps the most impressive composition on the disc is the Grand Fantasia, Op. 116, Oberons Zauberhorn, with its depiction of a storm at sea. The ‘storm’ is constructed as an introductory unit tracing a chromatic ascent (replete with bass tremolandi combined with chromatic scales and arpeggiated diminished sevenths), leading to a prolonged dominant of E minor that is resolved at the climax, followed by an extended coda in which, as in the more famous storm from Beethoven's Sixth Symphony, the energy subsides very gradually. One is also reminded of the first movement of John Field's Piano Concerto No. 5 in C major, h39 (L'incendie par l'orage), which preceded Hummel's effort by twelve years, and which was in turn likely to have been inspired by Daniel Steibelt's third concerto. Hummel's effects are more ‘graphic’ than Field's, though Field does insert quick glissandi to represent lightning and reinforces certain effects with additional percussion (see Geneva Handy Southall, ‘John Field's Piano Concertos: An Analytical and Historical Study’ (PhD dissertation, University of Iowa, 1967), 119). Like Beethoven in the Sixth Symphony, Hummel sustains tonal ambiguity, whereas Field's storm is firmly rooted in C minor. As in the solo sonatas and chamber music with piano, the level of virtuosity in Hummel's variations and fantasies is often considerable and withstands comparison with the concertos – without ever reaching the dizzy heights of Hummel's two major works of 1819, the Sonata in F sharp minor, Op. 81, and the Piano Concerto in B minor, Op. 89.

The principal qualities of Inui's playing (on a Bösendorfer concert grand) are warmth and richness of tone, a fairly strict approach to tempo and refined execution. Faster figuration generally has more poise here than on the 2005 disc. One encounters only occasional unevenness or indistinctness, for instance in the left-hand figuration in the fifth of the Armide Variations and occasionally also in Les deux journées. Inui's right-hand dexterity is beyond reproach, with faultless broken octaves and arpeggios in the third variation of Les deux journées and similarly slick high-register passagework in the opening section of Oberons Zauberhorn.

The richness of tone emanates partly from the instrument and partly from the extremely close positioning of the microphones, to the point that Inui's breathing becomes audible. This and slightly noisy pedalling are vaguely distracting in the opening section of Oberons Zauberhorn, and the close sound, coupled with the instrument's sonority and power, caused me to adjust the volume downwards in certain obstreperous, even histrionic passages, during which I was reminded of Field's admonition, made in response to Alexander Dubuque's forceful rendition of the opening of a Moscheles concerto: ‘Do you know that there are limits in the manner of treating a piano?’ (quoted in Southall, ‘John Field's Piano Concertos’, 46). The coda to the Quintor des nègres stands out in this way, as do the final sections of Oberons Zauberhorn and of Die Eselshaut. In the case of the latter, however, a rampage is only appropriate to the depiction of a ‘Bacchanal Tanz’. Excessive volume is also sometimes exacerbated by over-pedalling, as in the passage connecting the second (Larghetto) and third (Tempo di Marcia) sections of Oberons Zauberhorn, recalling the slightly rushed and jangled development section of the first ‘movement’ of the Fantasie Op. 18 that marred an otherwise outstanding performance on the 2005 disc. Such power does, however, befit the stentorian unison declamations punctuating the Quintor des nègres; and Inui's liberal pedalling of the subdued minore ninth variation of Armide seems highly apposite.

Inui's control of rhythm is extremely taut throughout, resulting in a delectable crispness that stands out in the principal theme of the Quintuor des nègres; it can be heard too in the array of spread chords, staccato melodies and accents in Variation 11 of Die Entführung, as well as in the dotted rhythms in the octave passage in Variation 6 of Les deux journées and in the march of Oberons Zauberhorn. Neatness also distinguishes Inui's management of more complex textures (Variation 2 of Armide) and underpins her carefully conceived juxtapositions of forte and piano dynamic levels, as in the third variation of Armide, which recalls the alternations of robustness and lyrical restraint in ‘The Bloodhound’ from the G minor Fantasie recorded in 2005. Inui's approach to tempo is consistent with her overall performance style, but I wished for more flexibility in the Larghetto of Oberons Zauberhorn and in the extended coda to the second section of Die Eselshaut. Subtle rubato effects enhance Inui's handling of the cantabile melody in the slow minore variation of Armide. The eighth of the Cendrillon Variations (in C major) contains a triplet passage of quasi-Beethovenian improvisation, straying to A flat major and also to A major; Inui demarcates the latter key with a slight slowing of the tempo.

Liner notes in general vary enormously in terms of approach, coverage and competence. Heinz Sichrovsky's contribution to the present recording is among the most successful I have ever seen in reconciling comprehensiveness with salience and lucidity. Full details of the fantasies’ and variations’ operatic sources follow an informative biography of Hummel. Refreshingly absent are tedious descriptions of the decline in Hummel's reputation coupled with the usual threadbare debates about his standing relative to Beethoven, Schubert and others. Sichrovsky's effusive claim that Hummel's ‘book on playing the piano’ (meaning the Ausführliche theoretisch-practische Anweisung zum Piano-Forte-Spiel, vom ersten Elementar-Unterricht an, bis zur vollkommensten Ausbildung of c1822–1825) ‘revolutionised the playing of the instrument’ (3) is extravagant, but it is gratifying to read unqualified and unembarrassed references to ‘Hummel's genius’ (4) and to experience a frank enthusiasm for the works at hand rather than sense an implicit disappointment that the subject is not the more erudite realm of sonatas and concertos. Orthodoxy obtrudes only in Sichrovsky's casual likening of parts of the Cendrillon Variations to ‘fragments of Schubert (Variation 3), Chopin (Variation 5) or Schumann (in the bizarre Variation 4)’ (4). Such resemblances are simply not clear without fuller demonstration, and Variation 5 does not even vaguely anticipate Chopin's style. Nevertheless, with its informative notes and accomplished performances, this disc is strongly recommended as an important addition to the growing selection of recordings of the works of this centrally important figure.