Raid,
I just went and dug-out three of my Barnacks: 1932 D ( II ), 1933 F ( III ), and 1952 IIIf, s/n: 600xxx.
Tried all three at the same shutter speeds throughout their repsective ranges.
I don't find my IIIf significantly louder than the other two cameras.
All are unrestored, and have their original curtains, as far as I know.
The IIIf definitely has its original curtains, as they are all crackly and no longer light-tight.
I do have them in eveready cases for shooting, but don't think that quiets them very much.
As long as you don't hear "shreiking" or "squawking" from dry parts ( my Exakta squawks in cold temps!), I wouldn't worry about it.
I'm sure your IIIf is quieter than most SLRs...
I have noticed that cameras with Focal-Plane shutters make more noise than those with leaf-type ( Compur ) shutters.
I think my Contax IIIa is quieter than my Barnacks.
Regards,
Luddite Frank
( Just dug-out the Contax: definitely a quieter camera. Heavier too ! )