This rather well-known Gemara came up in the Daf earlier this week. It’s actually the earliest mention of any part of Kaddish.
I remember growing up and sitting in shul near people who literally screamed ‘yehei shmei Rabbah’. This practice was apparently encouraged at the ‘siyum shas’ last year (see my posts on ‘Jewish Evangelism’).
The problem is that it’s not the prevalent understanding of the Gemara. The language of the Gemara is ‘be-kol kocho’ which means ‘with all his strength’. Rashi and Tosafot both understand this to mean ‘with all his focus’. Rambam clearly differentiates ‘kol kocho’ from qol ram’. Tosafot also quote a Psikta which indicates that a loud voice is preferable, but it’s not clear if the Psikta argues with the Bavli or explains it, but it’s not how at least the Rishonim that I’ve seen understand it.
So for the sake of those of us who like davenning without the howling, let’s be someich on Rashi, Tosafos and Rambam.