Sometimes the shift produced consonants that were pronounced differently (allophones) depending on the context of the original. With regard to original /k/ or /kʷ/ Trask says:
"The resulting /x/ or /xʷ/ were reduced to /h/ and /hʷ/ in word-initial position."
Many of the phonemes listed in the table represent can appear lengthened or prolonged under some circumstances, appearing in some daughter languages as geminated graphemes. The phenomenon is therefore termed gemination. Kraehenmann says:
"Then, Proto-Germanic already had long consonants … but they contrasted with short ones only word-medially. Moreover, they were not very frequent and occurred only intervocally almost exclusively after short vowels."
The phonemes /b/, /d/, /ɡ/ and /ɡʷ/ were stops in some environments and fricatives in others. The pattern of allophony is not completely clear, but generally agrees with the patterns of voiced obstruent allophones in languages such as Spanish. The fricatives merged with the fricatives of Verner's Law (see above). Older accounts tended to suggest that the sounds were originally fricatives and later "hardened" into stops in some circumstances. However, Ringe notes that this belief was largely due to theory-internal considerations of older phonological theories, and in modern theories it is equally possible that the allophony was present from the beginning.
Each of the three phonemes /b/, /d/, and /ɡ/ had a different pattern of allophony from each of the others, but in general stops occurred in "strong" positions (word-initial and in clusters) while fricatives occurred in "weak" positions (post-vocalic). More specifically:
- Word-initial /b/ and /d/ were stops and .
- A good deal of evidence, however, indicates that word-initial /ɡ/ was, subsequently developing to in a number of languages. This is clearest from developments in Anglo-Frisian and other Ingvaeonic languages. Modern Dutch still preserves the sound of in this position.
- Plosives appeared after homorganic nasal consonants:, . This was the only place where a voiced labiovelar could still occur.
- Gemination produced, . This rule continued to apply at least into the early West Germanic languages, since the West Germanic gemination produced geminated plosives from earlier voiced fricatives.
- /d/ was after l or z. Evidence for /d/ after /r/ is conflicting: it appears as a plosive in Gothic waurd "word" (not *waurþ, with devoicing), but as a fricative in Old Norse orð. /d/ hardened to in all positions in the West Germanic languages.
- In other positions, fricatives occurred: Singly after vowels and diphthongs, and after non-nasal consonants in the case of /b/ and /g/.
Other articles related to "allophones, allophone":
... in how orthographies represent these allophones ... used in the table represents the aspirated allophones as th, kh, and tsh ... orthography represents the unaspirated allophones as d, ɣ, and dz and the aspirated allophones as t, k, and s (Scancarelli 2005359–62) ...
... u Mid e o Low a These six vowels are characterized by several different allophones depending on the phonetic environments in which they occur (initial/noninitia ... The lowest and most central allophones occur in unstressed closed syllables ... According to Shipley, (a) and (y) have allophones that almost converge once they have centralized, (i) and (u) have allophones that barely centralize and ...
... may occur as /n/'s allophone before, when speaking quickly ... These are commonly viewed not as independent phonemes but as either (1) consonantal allophones of "medial" high vowels (i.e ... Some linguists prefer to classify as allophones of one of the other three series ...