In Sindarin and Noldorin, the combination [ŋg] became [ŋ] initially and finally, a sound change Tolkien mentioned in The Lord of the Rings appendices:

• NG represents ng in “finger”, except finally where it was sounded as in English “sing” (LotR/1114).
• ng remained unchanged [in Sindarin] except initially and finally where it became the simple nasal (as in English sing) (LotR/1115).

Since much earlier any initial [ŋg-] became [g-] in isolated words, the sound [ŋ-] was preserved initially only in the grammatical soft mutation of words that primitively began with [ŋg-]. The main example Tolkien gave was nguruthos, the lenited form of S. guruthos “death-horror” in the phrase S. le nallon sí di’nguruthos “here overwhelmed in dread of Death I cry” (LotR/729; RGEO/64), which was derived from primitive √ÑGUR + √THOS (PE17/95).

One major challenge in analyzing this sound change is that Tolkien represented both [ŋg] and [ŋ] orthographically as ng, meaning this sound change was not reflected in spelling. Tolkien mentioned this sound change so frequently, however, that there is little doubt it occurred:

• Final [ȵg] similarly, but perhaps later, also became [ŋ] before the end of the Gondolic period, but since the alphabet possessed no sign for isolated [ŋ], the spelling with g, transcribed ng, remained unchanged (Feanorian Alphabet, 1930s, PE22/35).
• While the substitution of n for ñ cannot be referred to the speech-feelings of the Exiles, since they acquired the Sindarin language as cradle-speech and colloquial tongue, and in S. both free ñ (finally) and initial ñ (in grammatical collocations) were frequent (second version of Tengwesta Qenderinwa [TQ2], circa 1950, PE19/77).
• Ng represents the same sound as E. ng; that in sing finally and initially as in nguruthos (Vol. II, p. 339), otherwise as in finger (Road Goes Ever On, 1967, RGEO/63).

Unlike other nasal-stop combinations, where [mb], [nd] became [mm], [nn] medially as well as finally, the sound change [ŋg] > [ŋ] did not occur medially between vowels, though it could sometimes occur in clusters of three or more consonants:

• In late Exilic [ŋg] suffered no further change. g thus represents [ŋg] except finally, where it is [ŋ]. [ŋg] has since remained before r, l, but became [ŋ] before other consonants, as Angband = [aŋban]. Before a main stress [ŋg] is sometimes in Toleressean reduced to [ŋ], but this is not normal (Feanorian Alphabet, 1930s, PE22/36).

Given the orthographic conventions, determining exactly when this sound change did and did not occur is difficult. It seems likely that [ŋg] and [ŋ] were allophonic combinations, much as they are in English, with pronunciation conditioned by where it appears in the word. Even when it was pronounced as a single [ŋ], it seems likely it was perceived as a cluster /ŋg/, as indicated by plurals of words ending in -ng:

• S. and N. Enfeng plural of S. and N. Anfang “Longbeards” (WJ/10; Ety/ÁNAD, SPÁNAG).

This plural behaves like words ending in clusters and not single consonants. Compare:

• S. nern plural of S. narn “tale” (MR/373).
• S. bair plural of S. bar “house, home” (PE17/164).

Conceptual Developments: Given the orthographic conventions, it is also hard to say whether this sound change occurred in the Gnomish and Early Noldorin of the 1910s and 1920s.

@@@ GS/§4.200, GS/§4.202