The API 512v is a mic / line / instrument preamp, world famous for its ability to provide a low noise (-129 EIN) and unusually good sounding front end for all types of audio applications.
Sonically, it delivers the instantly recognizable API sound at an affordable price, and in the scalable API 500 Series format. Offering an impressive 65 dB of gain, the 512v includes front panel Variable Output control, switchable 3:1 output transformer selection, phantom power, switchable polarity, -20 dB pad, and Mic or Instrument/Line selector. The front panel Combo-style XLR and 1/4 inch connector combined with rear panel mic access allows for additional flexibility when installed into an API lunchbox®, API's 10 position 500V vertical rack, or into an API console.
The API 512v remains faithful to the circuit designs of API's founder Saul Walker. Artfully combining those circuits with API's proprietary transformers and the incomparable 2520 op-amp, the 512v is a highly musical and rich-sounding analog mic pre, equally at home in commercial recording spaces as it is in smaller home studios. Fully featured and still hand assembled, the 512v exhibits the reliability, long life, and uniformity which are characteristic of all API products.
These merchants probably sell this module. Huh?
API 512v 500-Series Discrete