When thinking of the guitar these days, the Spanish "school" of Segovia and other great names in the 20th century is likely to be uppermost in the mind. Spain and the guitar are justifiably inseparable, but in the first half of the 19th century a so-called "Guitaromanie" in Europe saw its focus in Vienna, then the capital of the Austrian Empire. Instrument makers such as Johann Georg Stauffer vied for the finest sound and innovated in ways of constructing guitars, and composer/players such as Mauro Giuliani became the music stars of their day, touring and making their fortunes throughout Europe.

Johann Kaspar Mertz also toured widely, and his music reflects the influence of Schubert, Mendelssohn, Liszt and others, placing his stylistic character more firmly in the Romantic period than would previously have been associated with the guitar. His marriage and professional association with the pianist Josephine Plantin would no doubt have had its effect on this assimilation of styles, and with his choice of the ten-string guitar for his solo performances Mertz was more able to compete with the range of the piano at concerts. Published editions of his music needed to be as commercially viable as possible, and so these were designated as for the more conventional six-string guitar. This recording is therefore the first to present Mertz's music on an instrument he would have used.

The results in terms of colour and depth of sound are quite remarkable. The added bass strings not only add a convincing reinforcement to the fundament of harmonies, but also free up the mid and treble range so that the instrument seems to project an enhanced clarity throughout. Pictures show a guitar with a double neck and the additional four strings on an unfretted fingerboard. This must be tricky to play well, but Frank Bungarten's technique is very much up to the virtuoso demands of Mertz's writing.

There are of course some typical guitar 'fireworks' in pieces such as the Harmonie du Soir (Grand Fantasie), but for me the highlights are as much in the refinement and vocal quality of the polyphonic interactions. The Orgelfuge is a good but rather academic example, but listen to the different voices in the arrangement of Schubert's Aufenthalt and you'll hear what I really mean. Not only is the vocal line nicely etched, but the colour and character of each response below is a crucible of delights.

The familiarity of the Schubert tunes gives us insights into the ways in which Mertz solved the problems of transcribing piano music for guitar and made them very much part of his instrument's idiom. The freedoms expressed in something like the Fantasie hongroise then come as more breathtaking, Mertz joyously revelling at the top of his game in technical and expressive composing and making it easy for us to understand the massive popularity of the guitar in his time.

Frank Bungarten's notes for this recording also deserve a mention, bringing the instrument building techniques of the past right into the present and reflecting for instance on innovations by Stauffer that have translated directly into the design of flagship rock music instruments such as the Fender Stratocaster. This is a very fine recording of some hugely entertaining music, and will be a 'must hear' for all guitar fans and players.

– MusicWeb International (Dominy Clements)