Symphonie nº 3 "avec orgue" / Concerto pour piano nº 4

Your first instinct here is to get all excited about the concept. Not only are the orchestral parts for both Saint-Saens concerti played on dusted-down 19th century instruments, but the Organ Symphony is taped at the church of Saint Sulpice in Paris, with the 'Titulaire' Daniel Roth himself on the bench of the finest Romantic-style French organ on the planet. On the surface, it all reeks of a new authenticity hitherto unexplored in this repertoire.

Trouble is, the Organ Symphony was actually written for an English-style concert hall organ in London. What's more, Saint-Saens advised a harmonium be used if an organ wasn't available, which says a thing or two about his design. A concerto this isn't; the organ is really only used to colour the orchestral conversation and throw in a few transitional chords.

Which, to add a further twist, is precisely where this recording comes up trumps. The Cavaille-Coll organ at Saint Sulpice has a breathy weight which allows it to meet the tight, textured and translucent sounds of the period strings and brass head-on without simply obliterating them.

In that, Roth's choice of stops is vital. At the start of the Adagio and at 2.46 and 2.53 in the Maestoso his registrations seem to be born from within the prevailing orchestral mood, but still you feel the immense power of the instrument, like a tidal wind. In the big chord-fests he really puts his foot down, blowing most other in-situ recordings out of the water including the recent Philadelphia disc (which features Roth's opposite number over at Notre Dame, Olivier Latry). And still you hear the instruments.

It's enough to make this Organ Symphony recording very nearly the best yet. But hang on, weren't we talking earlier about it effectively being an orchestral work? Mercifully Roth's son François-Xavier delivers on the podium; he chooses his tempi well, creates intense focus in his strings and winds (in slow and fast passages) and generates acute cumulative momentum - almost as if his players are winding each other up.

The Concerto, recorded over at the Opera-Comique, doesn't come off quite so well, with the orchestra sounding rather more mannered and foursquare. Pianist Jean-François Heisser gets a sharp but ringing tone from his 1874 Pleyel, but he's no Stephen Hough in the Allegro vivace, where the gags and cross-rhythms simply don't come off. But that won't stop many from cherishing this disc for the Organ Symphony, and looking out for more from the same source.