I'M going to be both general and specific here about the exhilarating concert given on Tuesday night as part of the Cottier Chamber Project by host ensemble Daniel's Beard, an infinitely flexible and ad hoc group that, for this performance of two string quartets by Shostakovich and Beethoven, was represented by violinists Alastair Savage and Elita Bungard, viola player Andrew Berridge and cellist Tom Rathbone, all members of the RSNO or BBC SSO.

The presence of these four musicians – all familiar faces and characters, all stepping out of the large canvas of their orchestral roles in national companies to make chamber music together simply because they want to play together – was emblematic of why the Cottier project was created in the first place and what it has come to represent in just two seasons: so simple, so profound and so packed with implications.

As for Tuesday's performances, they were brilliant, with a meaty and sinewy account of Beethoven's Harp Quartet where, towards the close of the first movement, responding to one of the most amazing moments in all music, Alastair Savage exploded into a torrent of teeming arpeggios, over which Elita Bungard sent the great theme soaring skywards. Breathtaking.

Then, in a gripping performance of Shostakovich's great Seventh String Quartet – a terse, elliptical work which absolutely suited the bone-dry Cottier acoustic – the four musicians cut straight to the heart of the piece with playing that was appropriately conspiratorial, private and secret. Nobody ever outdid Shostakovich at stealth, ambiguity and mutter-mode. It was all here.

HHHH