The JC reeds come in lots of voices and can be altered further to change their tones and volumes a bit. There are several threads on this forum about tuning JC reeds.
For a starting point The reeds are labeled. LV or MV as in Loud Voice and Medium Voice. Add DR to that for double reed. Then a series of numbers pertaining to the gauge of the reed.
Beyond the reed itself the volume of your call will be determined by the dimensions and materials of the call. Commonly, the longer the barrel the wider the opening at the end needs to be. Also a decent of taper from the reed to the end. Be it stepped of smooth I don't care. They both work.