This is music for friends, and these Oslo musicians clearly enjoy playing together; the string quartet members seem especially well matched. In both works Leif Arne Pedersen chooses largely to eschew the vibrato of older recordings (and, apparently, of Brahms’s clarinettist, Richard Mühlfeld), allowing a gain in clarity that the string players don’t always take advantage of by drawing out the sap of the inner parts. Their speeds are just sufficiently brisk to prevent the Mozart from drifting into an Ovaltine haze as (is this wholly unfair?) clarinet quintets are wont to do.

Pedersen is mellifluous to a fault, however, and he seems to draw the first phrase of the second movement with exquisite calligraphy rather than living within it. An intimate yet ambient acoustic elides the cello presence and draws a further veil against the close listening ear. The Norwegians play with nigh-perfect intonation, at least until the climax of the slow movement of the Brahms, but then so do Sabine Meyer and the old gold of the Wiener Streichsextett (in the Mozart) and also the Alban Berg Quartet (the Brahms). They weigh each phrase, and in leaning into the Minuet of the Mozart find a gentle melancholy that eludes the perky Norwegian account. The Brahms is again neatly turned but at points of transition the Norwegians tend to flick a switch where Meyer and friends open a window.