The Magen Avraham (ad loc., 2) quotes from the writings of the Arizal that congregants should recite the introductory passage out loud and the middle passages quietly along with the leader. The Taz (1) writes that there is nothing wrong with reciting the introductory and middle passages, although does not require it. Interestingly, the first Lubavitcher Rebbe writes in his Shulchan Arukh Ha-Rav (125:1) that the proper practice is according to the Shulchan Arukh above but that some have the practice of following the Arizal.
Click here to read moreThe practices that I've seen are as follows, very roughly following the Ashkenazic and Sephard (i.e. Chassidic) versions of prayer albeit with a great many exceptions:
- Recite just the introductory passage out loud but not the middle passages at all (Ashkenazic, cf. Arukh Ha-Shulchan, ad loc., 2; Mishnah Berurah, ad loc., 2)
- Recite the introductory and middle passages out loud (Sephard)