When signers whisper or shout, their phrases are expressed in a phonetically marked way. Proximalization and distalization have already been discussed in PHONOLOGY 3.1.3.2, and here, we provide a brief description of other phonological specifications observed in both modes. Note that generally these processes are not considered part of the grammar of a language, as they are part of phonetics/individual articulation, and because they are likely to be very similar across sign languages. Still, it is worth paying attention to deviances of the standard articulated forms.
As for whispering, one study describes that the signing space in general is reduced, as the head of the signer generally moves closer to the hands and/or the hands move closer to the body. More specifically, the head can be tilted forward, and the shoulders can be moved forward. In addition, non-manuals can be realized in a less pronounced way. Manual adaptations are a loss of movement, a change of location and/or orientation, and weak hand drop (PHONOLOGY 3.1.4).
As for shouting, the signing space is enlarged, by increasing the distance between the hands, and between the body and the hands. Head movements, body movements and non-manuals (including mouthings) can be more pronounced. Concerning manual adaptations, the author observed that the location of a sign was often more forward and higher than in the citation form. In addition, handshape changes were strikingly larger. He further noted that articulator-internal movements were sometimes added to signs which only had a path movement in their citation form (see also PHONOLOGY 3.1.3.1).