Question

ɣ The fricative version of [g]. English does not have this sound. It is the most common sound of Spanish g (except when it is at the beginning of an utterance (after pause) or after a nasal consonant): hago, amigo, mi gato. Some dialects of Spanish have the articulators closer than others and thus this g sounds "harsher".

Accepted Answer

Voiced Velar Fricative http://en.wikipedia.org/wiki/Voiced_velar_fricative

Symbol	ɣ
Name	Voiced Velar Fricative
Notes	The fricative version of [g]. English does not have this sound. It is the most common sound of Spanish g (except when it is at the beginning of an utterance (after pause) or after a nasal consonant): hago, amigo, mi gato. Some dialects of Spanish have the articulators closer than others and thus this g sounds "harsher".
Ref	http://en.wikipedia.org/wiki/Voiced_velar_fricative

G Fricative Velar Spanish O ɣ Voiced Version