From Wiktionary, the free dictionary
From 生 (nama) + 声 (koe). The koe changes to goe as an instance of rendaku (連濁).
なまごえ • (namagoe)
- real person's voice (as opposed to being pre-recorded; or as opposed to being computer-generated)
- 生声実況
- namagoe jikkyō
- Let's Play video with narration in a real person's voice (as opposed to ゆっくり実況)