Can't say about minimum but i can tell ya first call i made with mine, it almost blew my eardrums off volume was about 3/4 of the way up lol. Does get nice and low enough so i can hear without that happening though.
Hmm @Law actually the speaker is not that loud on max. volume. But when u stand beside someone he can hear the call very clearly.. But it really isn't loud... It's solid quality..