Zildjian's S Family (B12 alloy) is stamped from preexisting sheets, similarly to many Paiste lines. It's then fully lathed and hammered in the same manner as, say, a Zildjian A Custom. In fact, if you read Zildjian's production descriptions of S's and A Customs, they're identical on every count except their alloy (B12 vs. B20, respectively) and their condition of origin (stamped vs. cast, respectively). They otherwise receive the same craftsmanship throughout their stages of development.It's my understanding that Paiste still employs an outside supplier for all their metals; discs made to their specifications.
Is the same true for Zildjian S cymbals? Sabian B8s?
I have no insight to offer on Sabian. I've never owned anything with a Sabian logo.