I am currently studying Amdo Tibetan. In this language the voiced velar fricative [ɣ] is reported to occur as the first sound in some syllable-initial consonant clusters. More specifically, this sound occurs only before voiced consonants. (Before voiceless consonants this phoneme surface as voiceless [χ] or [h].)
Here are some examples of phonetic transcriptions of words starting with this sound (taken from various academic papers):
- [ɣza ɦda wa]
- [ɣgon pa]
- [ɣlab raŋ]
There are many papers written on the phonology/phonetics of Amdo Tibetan and all of them use the IPA symbol [ɣ] for this sound. This so-called "pre-initial" sound is quite common in Amdo Tibetan and I hear it quite often when listening to the recording that accompanies my Colloquial Amdo Tibetan textbook, for example.
The problem is that no matter how hard I listen, I can't seem to hear that this is a velar fricative. In fact, I don't hear it as a fricative consonant at all. Instead, it just sounds like a very short [ə], or at least some other kind of central vowel. Thus, instead of [ɣlab raŋ] I hear something like [əlab raŋ].
My native language is English and a voiced velar fricative is not a sound I can produce naturally, but I have read a description of it in "A Course in Phonetics" and I've listen to a recording of this sound on Wikipedia (see here: http://en.wikipedia.org/wiki/File:Voiced_velar_fricative.ogg). Yet to me this sound does not sound at all like the sound that Amdo Tibetan linguists are transcribing as [ɣ].
My question is: Is this [ɣ] sound actually being pronounced more like a [ə] (or some similar vowel sound-- in which case the transcriptions are "inaccurate"), or do I just hear it as [ə] because I am unaccustomed to hearing a syllable-initial [ɣ]? Or perhaps this velar fricative is being pronounced so lightly that it's fricative nature is not easily heard? Can I use software such as Pratt or WaveSurfer to figure out which sound is actually being produced?
P.S. I can upload a sound file if that would help.