Sunday's coffee concert on an airless, sultry morning on Holywell St was an all-Mozart programme, first a string quartet and then one of his piano concertos scored a quattro – ie for piano soloist and string quartet. On stage we had the Adderbury Ensemble, the band that's the mainstay of this Sunday morning chamber music series, and brainchild of Chris Windass and his associates; Mr Windass being also the promoter of these Coffee Concerts. The personnel mixes and matches to suit the scheduled programme and players' commitments, but I'll call this the Adderbury 'A-Team' since Messrs Windass, David Le Page, Jenny Sacha and Jane Fenton plus pianist Viv McLean are just about the most faithful of all the component players.

I hadn't heard Mozart’s 'Hoffmeister' String Quartet for some time. Unlike many of Mozart’s other string quartets this is not part of a set and so it stands alone. Hoffmeister was a friend and colleague of Mozart’s and also an idiosyncratic music publisher. Mike Wheeler's ever-helpful programme notes talked of its "elusive tone" and "ambiguous character" and immediately after the opening bars, the ready manner in which the music jumps from the key of D to that of B minor illustrates how it's hard to characterise this work.

Generally with Mozart one has a sense of his emotional intention, if not his actual mood when writing down the score. Here these things are tricky to gauge owing to this key shift and others that follow later. There’s a bit of an operatic quality to this work to my ear, and I enjoyed the precision of the ensemble's playing and also their balance, with lots of give-and-take. They dug into the music in the 'menuetto', emphasizing that this is a dance. The minor-key triplet variants of the theme, tossed around among the instruments, provided a more circumspect contrast. I liked also the tender, eloquent opening of the 'adagio'. But above all, despite the beauty of the lyrical lines, there’s an underlying foreboding, a nervousness and restless quality in the work that this performance captured so well.

The Piano Concerto No. 12 in A was originally scored for two oboes, two bassoons (optional), two horns, and strings, though Mozart left notes for its presentation, as here, a quattro. It's the middle one of a set of three (Nos. 11, 12 and 13) that Mozart wrote at the back end of 1782 at the age of 26 in Vienna, and composed for a large public. I think this one is the most beautiful of the three. From the opening 'allegro' springy rhythms and melodies were shaped with obvious affection by our players. The cello playing of Jane Fenton, elegant in black with spangly glitter to her jacket and boots, is a delight to watch in that few cellists convey such clear joy in the music; nothing showy, just intense appreciation.

When Viv McLean's piano entered, I thought there was a slight problem with the volume of the instrument. The five musicians were rather cramped on the dais, with Mr McLean well to the rear. I'm not sure whether he was aware of this and consequently compensated just a shade too much; but to my ear the piano sound was a little loud. In the quietest moments of the 'andante', there were also two or three notes in the 'adagio' where you could just about hear the actual hammer action as he depressed the keys. But there's no question Mr McLean has sparkle in his fingers also. This is not lightweight Mozart, for although the music has its frothy aspects, Mr McLean did not pass over depths, and his mining of them was not signposted, and the 'allegro' as a whole (including I think Mozart's own brief cadenza) was integrated and crisply delivered; this was music-making both communicative and intelligent from the ensemble that enjoyed an organic ebb and flow. A Sunday morning treat!