Mozart's Quintet, like his Clarinet Concerto, survives only in an arrangement his publisher made after his death. As has been realized only recently, he wrote them for a clarinet with an extra joint at the bottom which added a third to the range. When this instrument failed to catch on, Mozart's publisher adjusted the very low notes to make the solo part playable on standard clarinets. The most recent Eulenburg score of the Concerto includes a page showing Alan Hacker's suggestions as to what Mozart himself probably wrote, and they seem to me wholly convincing. Oddly enough there are not nearly so many of these low notes in the Quintet and no adjustments at all are needed in the slow movement or in the main section of the Minuet. But the finale does benefit from Hacker's use of a modern extension on his early nineteenth-century clarinet. The stringed instruments on this record would also have met with Mozart's approval, and the result is an interesting performance of unusual authenticity. Both repeats are made in the first movement. The tempo of the slow movement does seem a little too slow to me, as does that of the Adagio variation in the finale, but the playing is nicely expressive and I liked Hacker's modest decorations in the slow movement reprise.
The other two pieces were also meant for an extended clarinet, but Mozart never finished them. This need not be much regretted as regards the first one, but the much longer fragment with parts for basset horn and only three stringed instruments is lovely. Why did Mozart lose heart? Duncan Druce's completion is convincing and allows us to get to know some beautiful music. Sound quality on this record is first rate, as is the balance.'