JS Bach’s sonatas for transverse flute and harpsichord throw up all sorts of awkward questions for musicologists, not least the issue of whether Bach actually composed some of them at all. The most problematic sonata with regard to that most niggling of niggles is BWV1020, which isn’t even in Bach’s style. However it’s a particularly enjoyable piece, not least for its dulcet Adagio, so I immediately warmed to Peter Holtslag and Ketil Haugsand for shrugging off this authenticity irritation in the name of good music, and including it in their programme of the sonatas with obligato harpsichord.

It’s an authenticity-rich recording too, not least for the instruments themselves, because, while Holtslag performs the majority of the sonatas on a modern copy, BWV1030 is performed on an original solid ivory, silver-keyed flute dating from Bach’s Leipzig period. You can admire this beauty on the disc’s cover artwork, photographed up-close and dismantled to display its three pitch-altering corps de recharge; and while the odd muffled note during the sonata suggests it isn’t entirely easy to coax into perfect tone, it’s lovely nevertheless and makes for an intriguing start to what is throughout a thoroughly stylishly performed recital.

Listening immediately afterwards to Pauliina Fred and Aapo Häkkinen’s programme for Naxos of BWV1030 35 takes some initial ear adjustment. Both instruments are more closely miked, producing a much brighter, almost overwhelming sound, and in BWV1030 Hakkinen’s harpsichord is so noticeably to the fore that it’s rather to the detriment of the flute. Once you’ve acclimatised, however, there’s plenty of good stuff, from the slightly more playful mood of the whole to the greater instrumental variety. For instance, where Holtslag and Haugsand stick to their double-manual harpsichord for BWV1033 (and indeed throughout their programme) and thus fashion the basso continuo part more idiomatically to match, Häkkinen entertainingly switches to the lute-harpsichord, keeping the accompaniment sparse and chordal. He also switches to the clavichord for BWV1035.

So there’s an element of horses for courses here. Some will enjoy the greater subtlety and the historical instrumental interest of Holtslag’s recital but, if it’s more obvious contrasts you’re after, the Naxos disc is worth considering.