AKG C 451 B

Small diaphragm cardioid condenser mic, with attenuation settings at 0, -10 and -20dB, and bass rolloff at 0, 75 and 150Hz. Used to capture a Martin acoustic for Oceania.
[product page]

Mentioned in a MIX Magazine article on 2011/08/01:

Billy had just acquired an amazing vintage Martin that we miked with a Soundelux e251, and an AKG 451 and 414. These were all amped with a modified Neotek sidecar and summed on a Neve 5088 mixing board using the Roy Thomas Baker summing method.