All Ears
From Halopedia, the Halo wiki
All Ears
All Ears is an Achievement in Halo 3: ODST. It is unlocked when you find 15 Audio Logs in Campaign Mode, alone or with another ODST. It is worth 30 Gamerpoints.[1]
It is represented by a blue square with audio lines going across it, with 15 in the lower-right corner, and a picture of the Superintendent with he's eyes wide open.
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