Phonetically speaking it should be a soft 'g' as in giant. In English, when a 'g' is followed by 'e', 'i' or 'y' it has a soft sound. When followed by 'a', 'o' or 'u' it has a hard sound.
Actually, according to Ursula Le Guin, the correct pronunciation is 'Ghed'. Not 'Jed'.
4th paragraph, last sentence of the provided link.