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14. Must the blower and listeners be in the same area/building/room?
One can be Yotzei Shofar even if he is not in the same area as the blower, so long as an echo is not sounded. Thus, a person can blow Shofar for a family from outside their home and have them be Yotzei by hearing the blows from inside. Likewise, people may stand outside the Shul and hear the blowing and be Yotzei. Likewise, the blower may stand outside the Shul and be Motzi those inside the Shul. Regarding if one can be Yotzei outside if the blowing is taking place in an underground, or basement Shul-see Q&A!
May one listen to Shofar outside a Shul which is within a basement or bunker [Miklat]?
Any building which is majority in the ground is assumed to release an echo to those outside and hence follow the same laws as stated above regarding a place that echoes. If, however, the basement has windows near its roof, and the windows are above ground, then it is questionable whether it releases an echo to those outside. Practically, due to this, it is proper that all the listeners of Shofar enter inside the Shul if the Shul is found in a basement or bunker. Nevertheless, by women there is room to be lenient to allow them to remain outside if the windows are open and they are sure they are hearing the sound of the Shofar and not the echo.
May one blow Shofar in a building that has acoustic ceilings?
This matter requires further analysis.
 Admur 587:5; Taz 6587:1; Chayeh Adam 141:5; M”E 587:1; Kaf Hachaim 587:6
 Piskeiy Teshuvos 587:1
 Admur 587:1; M”B 587:2
 Biur Halacha 587 “Oa” leaves this matter in question. See Piskeiy Teshuvos 587:1 that if the windows are closed it certainly has the status of an area that echoes to those outside.
 In a case that the Ezras Nashim is on the second story of the Shul and the Shul is underground, this matter requires further analysis. [Piskeiy Teshuvos ibid; Mikraeiy Kodesh 8 footnote 216]