Xaudia now offers a service to convert Calrec 6-series microphones to Phantom Power.
These microphones sound nice but the noise floor can be too high to be of much use, and they also need a specific power supply rather than standard 48V phantom. In addition, they are difficult to service because the high impedance section of the circuit board is potted in epoxy resin – including an electrolytic capacitor. If anything goes bad in there then it is near impossible to replace.
The Xaudia upgrade includes swapping the entire circuit board and fitting a new, low noise PCB which runs on standard 48V phantom power, and switching the DIN connector to an XLR socket.
The cost is a fixed £99. You can read further details here at the Xaudia blog.