On last august I upgraded my ’s right receiver from P to UP and, as you know about UP/HP case, it was necessary to get a shell because the UP receiver must be encapsulated within its shell in one single solid piece. The shell was very big: referring to this47 gallery, it was the “full shell” one and it filled all the right ear’s concha (both cymba and cavum, see here29).
Recently I’ve just upgraded left receiver as well from P to UP but in this case the shell is the “cShell” of the above gallery.
I’ve asked my audiologist why this big difference and he’s answered the factory decides the shells’ sizes, he just sends to it the mold of the ears.
I’m not fully convinced of his answer so I want to ask you if you experienced something like that with UP shells and, if yes, if you can tell me the reason of this difference.
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