For sale is an. Advanced Audio valve microphone bundle, consisting of. Advanced Audio C12 – fully working. 1 x Advanced Audio valve power supply (shared between both microphones). Shock mount, carry case & pop filter included. Both microphones use the. Only one microphone can be powered at a time. Condition & Technical Notes. And is performing perfectly. Valve response graphs will be uploaded. Clean, open sound with classic C12-style top end. Used in a smoke-free studio environment. I’ve been advised it should be a. Relatively simple fix, but I haven’t had it serviced. Bonus / project mic or for spares. Tested with the C12. Shared PSU as per Advanced Audio design.