As we have seen, the teru’a alludes to sorrow, brokenness, and tears. Over the course of time, however, a doubt arose as to what is the optimal sound of the teru’a. Some congregations blew medium-length sounds, reminiscent of someone sighing (what we now call shevarim). Other congregations blew shorter blasts, like someone heaving with convulsive sobs (what we now call teru’a). Still others blew both types of blasts, imitating a person in pain who starts by sighing and continues with sobbing (what we now call shevarim–teru’a). Even though one fulfills the obligation with any of these variations, it can seem to unlearned people that there is a dispute about this matter.
Therefore, R. Abahu instituted that in his city (Caesaria) all three types of teru’ot would be blown (Rosh Ha-shana 34a; R. Hai Gaon). There was another reason for his ordinance: each type of teru’a has a unique value, and it is proper to hear all types of teru’a (Zohar III 231b). This ordinance was then accepted by all communities; ever since, the medium-length blasts are called “shevarim” and the short blasts are called “teru’a.” The order of blowing is as follows: We begin with three sets of tashrat (teki’a, shevarim-teru’a, teki’a). We follow this with three sets of tashat (teki’a, shevarim, teki’a). We conclude with three sets of tarat (teki’a, teru’a, tekia) (SA 590:2).
Since R. Abahu’s ordinance was accepted, the obligation is no longer fulfilled by hearing only one type of teru’a. Rather, one must hear all three types of teru’a. Thus, even though according to the Torah we are obligated to blow nine blasts, nowadays we are obligated to blow thirty: nine for the three sets of tashat, nine for the three sets of tarat, and twelve for the three sets of tashrat.
There is still room to discuss whether someone who only knows how to blow a shevarim should recite a berakha before doing so. Those who follow Rambam would certainly say no, as nowadays it is uncertain whether this fulfills the obligation. It is possible that R. Hai and his followers would agree, since the shofar-blower is not following R. Abahu’s binding ordinance. In fact, BHL 593:2, s.v. “ve’im,” states this explicitly. It is also implied by Me’iri (Rosh Ha-shana 34a), who follows R. Hai Gaon but nevertheless writes that nowadays we cannot fulfill the obligation without blowing all three types of teru’a. On the other hand, some say that the berakha should be recited in this case, as the halakha follows R. Hai Gaon and his followers. For further discussion, see Harḥavot.