The essential difference in the Mozart quintet between the version for basset clarinet and that for soprano clarinet is more of tone than of text. Of the latter, there is only a handful of bars, such as bar 41, where the scale descends to C rather than rising to C, where the lowest third of the instrument is employed. As to tone, the basset clarinet is somewhat darker.
This music is about as close to perfection as music can get, its overall effect only lessened when the overall interpretation is not as limpidly and lyrically engaging as such as those by Reginald Kell and the Fine Arts Quartet or Jack Brymer and the Allegri Quartet. As example, if the Menuetto is taken slightly too quickly, the first trio lacks plangency. As second example, the final movement will seem a touch imbalanced if the four variations are somewhat hurried, and there is insufficient contrast between the allegretto tempo of the theme and variations, and the coda, which is allegro, hence, slightly faster. Without this being sensed, the intervening adagio has its effect made insufficient, and its intimation of the sadness that touches the pure lyricism that pervades the Quintet, is dulled.