Selmer USA CL301 Student Clarinet (Standard) CL301 Selmar Clarinet The use of carefully located tapers (conical) and straight (cylindrical) sections creates a smooth, consistent scale. Selmer CL Series clarinets enable musicians of all ages and abilities to produce a refined, resonant tone quality. The shape of the Selmer CL Series clarinet bore results in an instrument in tune with itself. Play a low G, add the register key to produce the D a twelfth above and check the pitch of both notes; they should register as in tune.