The following quarter-tone scale extends from A3 to D6; it contains relatively few problems for the clarinettist. However, somewhat weak conjunct sections of the quarter-tone scale are found across the "break" from the throat register to the clarion register (B-flat 4 to Dsharp 4).32 From B-flat 4 to C4 there are technical problems because of awkward finger placement requirements. From C4 to D-sharp 4 there are no practical fingerings for quartertones, since virtually the entire length of the instrument is employed. Cross fingerings can not be utilized. This is the same consideration that inhibits quarter-tone production below chalumeau A. Another section of the quarter-tone scale that is weak consists of pitches above B6. The altered air and embouchure pressure necessary to produce these pitches (often on different partials), as well as awkward fingerings make them treacherous, especially if approached quickly by leap.