Voiced velar approximant
The voiced velar approximant is a type of consonantal sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is ⟨ɰ⟩, and the equivalent X-SAMPA symbol is
The consonant is not present in English, but approximates to the sound of a 'g' with the throat kept open, or like making a 'w' sound without the lips touching. The voiced velar approximant can in many cases be considered the semivocalic counterpart of the close back unrounded vowel [ɯ]. ⟨ɰ⟩ and ⟨ɯ̯⟩ with the non-syllabic diacritic are used in different transcription systems to represent the same sound.
The symbol for the velar approximant originates from ⟨ɯ⟩, but with a vertical line. Compare ⟨u⟩ and ⟨ɥ⟩ for the labio-palatal approximant.
Some languages have a voiced velar approximant that is unspecified for rounding, and therefore cannot be considered the semivocalic equivalent of either [ɯ] or its rounded counterpart [u]. Examples of such languages are Catalan, Galician and Spanish, in which the approximant consonant (not semivowel) unspecified for rounding appears as an allophone of /ɡ/.
Eugenio Martínez Celdrán describes the voiced velar approximant consonant as follows:
As for the symbol [ɰ], it is quite evidently inappropriate for representing the Spanish voiced velar approximant consonant. Many authors have pointed out the fact that [ɰ] is not rounded; for example, Pullum & Ladusaw (1986:98) state that 'the sound in question can be described as a semi-vowel (glide) with the properties "high", "back", and "unrounded"'. They even establish an interesting parallelism: 'the sound can be regarded as an unrounded [w]'. It is evident, then, that [ɰ] is not an adequate symbol for Spanish. First of all, because it has never been taken into consideration that there is a diphthong in words like paga 'pay', vago 'lazy', lego 'lay', etc., and, secondly, because this sound is rounded when it precedes rounded vowels. Besides, it would be utterly wrong to transcribe the word jugo 'juice' with [ɰ] *[ˈχuɰo], because the pronunciation of that consonant between two rounded vowels is completely rounded whereas [ɰ] is not. (...) The symbol I have always proposed is [ɣ̞], the correlate to the other central approximants in Spanish, [β̞ ð̞] (Martínez Celdrán 1991, 1996:47). This coincides with Ball & Rahilly (1999:90), whose example for the three approximants is the Spanish word abogado 'lawyer' (see figure 1). Ball & Rahilly too criticise in a footnote the confusion between these symbols: 'The difference between an approximant version of the voiced velar fricative [ɣ], and the velar semi-vowel [ɰ] is that the latter requires spread lips, and must have a slightly more open articulatory channel so that it becomes [ɯ] if prolonged' (p. 189, fn. 1).
There is a parallel problem with transcribing the palatal approximant.
The symbol ⟨ɣ̞⟩ may not display properly in all browsers. In that case, ⟨ɣ˕⟩ should be substituted. In broader transcriptions, the lowering diacritic may be omitted altogether, so that the symbol is rendered ⟨ɣ⟩, i.e. as if it represented the corresponding fricative.