This paper reports work that is part of a larger project concerned with correlating differences in the perceived playing characteristics of musical wind instruments with physical differences between them. Here we focus on five different student model clarinets. Some of the practical difficulties of (i) directly measuring the bore profiles of the clarinets and (ii) measuring their input impedances are discussed. Results are presented which show significant differences in bore profile between the five instruments, leading to clear differences in the frequencies and magnitudes of their resonance peaks. In addition, some initial thoughts regarding playing tests designed to establish clarinetists’ perceptions of the instruments are considered