槽数
对于块形变幅杆：加工到指定表面上的槽数。变幅杆通常用两个相邻侧表面上的槽数来描述——例如，如果一个宽度方向表面有 4 条槽，一个厚度方向表面有 2 条槽，则该变幅杆称为"4 槽 x 2 槽"变幅杆。槽的总数为变幅杆两个相邻侧表面上槽开口的数量——在前面的例子中为 6 条槽。
对于带交叉槽的圆柱形变幅杆：变幅杆圆柱表面上槽开口数量的一半。（这与块形变幅杆中的交叉槽数量一致，因为圆柱形变幅杆可以由块形变幅杆加工而来。）
对于带径向槽的圆柱形变幅杆：变幅杆圆柱表面上槽开口的数量。
Number of slots
For a bar horn: the number of visible slots.
For a block horn: the number of slots machined into a specified surface. A horn would typically be described by the number of slots in two adjacent lateral surfaces — e.g., if a width surface has 4 slots and a thickness surface has 2 slots, then the horn would be described as a "4‑slot x 2‑slot" horn. The total number of slots is the number of slot openings on two adjacent lateral surfaces of the horn — in the previous example, 6 slots.
For a cylindrical horn with cross slots: one-half the number of slot openings on the cylindrical surface of the horn. (This agrees with the number of cross slots in a block horn, since the cylindrical horn may be derived by machining a block horn.)
For a cylindrical horn with radial slots: the number of slot openings on the cylindrical surface of the horn.
When determining the number of slots, any back slots or face slots should not be included.