Quenya Phonetics P31: final consonant clusters reduced

Q. final consonant clusters reduced; [-CC|-{ptk}s|-{xp}t] > [-C|-s|-t]

It is well known that Quenya only allowed five final consonants: n, t, l, r, s, and the cluster nt (Let/425; PE19/104; PE22/62; VT42/7). That means any other consonants and consonant clusters had to be modified when final. The number of possible combinations is large, but these changes can be reduced to three relatively simple rules:

Quenya Phonetics P29: short final [a], [e], [o] lost in long compounds

Q. short final [a], [e], [o] lost in long compounds; [-SSS{ăĕŏ}] > [-SSSø]

In Quenya, short final ă, ĕ, ŏ were lost in long compounds. Tolkien discussed this in the Outline of Phonetic Development [OP1] from the 1930s:

At end of long words, especially compounds, ă, ĕ, ŏ, reductions of ē, ā, ō (as described above), were also lost. Thus kwènedḗ > kwendḗ but móri-kwènedḗ > móri-kwènǝdĕ > móri-kwèndĕ > móri-kwèn(d), Q. Moriquen.

Quenya Phonetics P27: [ŋ] assimilated to following [n] after [e], [a], [o]

Q. [ŋ] assimilated to following [n] after [e], [a], [o]; [{eao}ŋn] > [{eao}nn]

In cases where velar nasal ñ [ŋ] survived before a dental nasal n, it likewise became dental so that eñn, añn, oñn > enn, ann, onn. Tolkien mentioned this in both Outline of Phonetic Development [OP1] from the 1930s and the Outline of Phonology [OP2] from the 1950s:

Quenya Phonetics P24: [-ai] became [-e]

Q. [-ai] became [-e]; [-ai] > [-e]

In Quenya a final -ai became -e. The most notable result of this sound change can be seen in the plurals of adjectives end in -a, as indicated in notes on Námarie from the 1960s:

final -ai in plural of adjectives > e (PE17/76).

These notes indicates this sound shift occurred in or shortly before the Tarquesta [TQ] period. This development can also be seen in words other than adjectives: