Rather than presenting their Beethoven set in a neat chronological series, the Belcea Quartet mix quartets of different periods on each CD, as the Alban Berg Quartet did some years ago. Also like the ABQ, these performances are described as being recorded ‘in concert’, but applause has been edited out and indeed there’s nothing to suggest live performance.

I’m particularly impressed by the Belcea’s close attention to dynamics. Beethoven, whose performance indications are more copious than his predecessors’ and contemporaries’, clearly related dynamics to form and phrasing, so the exactness of the placing of crescendos, the vivid distinction between piano and pianissimo, give the music an authentic life – illuminating the composer’s imagination. Similarly, the Belcea’s insistence that slurs denote a true legato helps enormously in conveying the music’s emotional import. Their playing may have a very different sound from the string quartets of Beethoven’s day but the way the music breathes and moves gives a clear picture of his intentions.

Nearly all the time the Belcea’s polish is a delight. But in the Presto movement of Op 131, where Beethoven has a number of jokes at the players’ expense, expecting them to dovetail rhythmic fragments at high speed, the effect is so smooth that the listener may be unaware of any humorous intent. More often, though, the Belcea are at their best in the scherzo-like movements – those in Op 18 Nos 1 and 6, Op 95 and Op 127 are outstanding, and other pieces of a light-hearted character are similarly alert, and dramatic or playful as appropriate.

Beethoven provided metronome marks for all his quartets up to Op 95. Some of his speeds are challengingly fast; for such pieces as the finale of Op 59 No 3 the Belceas, playing as quickly as they can successfully manage, create a genuinely brilliant, exciting effect. But there are a few places where attention to the marked tempi might have helped their interpretation. The slow movement of Op 18 No 1 is beautifully played but with a more flowing accompaniment the music would have made a greater impact. Similarly, at a faster tempo the second movement of Op 18 No 4 could have shown more of the scherzoso quality that Beethoven asks for. However, the moderately paced finale of Op 127 (with no metronome mark or tempo indication) is strikingly successful, with its finely balanced textures and sensitive legato phrasing. All in all, this promises to be an outstanding set – not the last word on these endlessly fascinating works, perhaps, but performances of great artistry and perception.