We have one toilet cistern which is terribly noisy to fill - you hear it
throughout the whole house and it would wake the dead at night-time - so
after n years, SWMBO has decided that Something Must Be Done (she's
now threatening to go to B&Q and just buy a whole new loo for me to fit).

ISTR the problem dates back to when we changed our DHW to a sealed,
mains pressure system throughout the house about 6 years ago. Can't
recall all the details now but I do remember changing the cistern valve
for a Torbeck job - I think that might have been because of noise but
can't remember.

Anyway, currently I have to have the service valve for this cistern
cranked right down, otherwise it's far worse - we get the most amazing
banging and reverberating noise from the pipework as the cistern fills.
As it is, with the service valve almost closed, it takes a very long
time to fill (7-10 mins) and the water still makes a hell of a noise (ie
hissing) during that time... and no matter how finely adjusted the
service valve, I can't avoid the almighty 'thunk' as the Torbeck valve
finally closes, when the cistern is full: and that if the hissing hasn't
woken her already, that certainly will!

So what to do?

My thought is that the Torbeck valve I've got is inadequate for the
water pressure (ISTR it's a fairly standard 2-3 bars) - I can't
particularly rememember any issues over pressure rating etc when I
fitted it, and would certainly have been wise to it had it been
mentioned or whatever. Are there specific versions for high and low
pressure or do they have swappable components?

I'm thinking of buying a new Torbeck valve and fitting that from
scratch: does that sound sensible or am I missing something?

Thanks
David