tekiyos al seder habrachos - brisker rav vs. chazon ish

Although the Ba’al haMaor writes that tekiyas shofar must be fulfilled in the context of tefila, the parameters of the chiyuv are not clear. Minhag Ashkenaz is to blow shofar only during the chazaras hashatz and not in the silent amidah (according to some Rishonim, the silent tefilah of musaf consisted of only seven brachos and did not reference malchiyos, zichronos, or shofaros). The Brisker Rav as well as R’ YB Soloveitchik held that one must be careful to be attentive and listen to every word of chazaras hashatz in order to fulfill the chiyuv of tekiyos in the context of brachos – one is “credited” with being yotzei the malchiyos , zichronos, and shofaros only by hearning every word of the shaliach tzibur. In the case of someone who will not hear the chazaras hashatz in its entirely, it seems according to the Brisker Rav that one gets no kiyum of tekiya al seder haberachos (though obviously one still has fulfilled the mitzvah d’oraysa of shofar). The Chazon Ish (siman 137) disagrees and writes that the chiyuv of blowing while reciting malchiyos, zichronos, and shofaros is not a chiyuv on each individual, but is a chovas hatzibur – i.e. the tzibur must schedule the blowing of shofar to occur in the context of brachos of tefila, but each individual does not have a specific chiyuv to hear those brachos. According to the Chazon Ish, if one entered shule in the middle of chazaras hashatz and heard tekiyos blown in their proper place, even though the listener missed hearing tefila, he/she fulfills hearing tekiyos al seder habrachos by simply by having heard tekiyos blown in their proper place.