I think I understand what you meant. "e" in your example negative sounds closer to "a" as in ate. In actuality, I think both "e"s should sound the same. The variation was probably due to accent differences.
【在 G***G 的大作中提到】 : do you feel difference between e in 'net' and e in 'negative'? : but they are /e/ in phonetic symbols. : is it strange, isn't it?