The Sennheiser long shotgun microphone ME-88 has quite a low output voltage (5mV/Pa) which is too low for, for example, a Sony V1. The solution is to build a pre-amplifier into the supply module.
I have removed the original circuitry from a K30AV module and replaced it by this pre-amplifier with a gain of 9:
Initally I've chosen the OPA177 because it draws only 2mA and it's fairly low noise at intermediate source impedances. However, it turns out that the OPA227 is doing an even better job. It draws 3mA but is ultra low noise which gives an outstanding performance. The amplifier operates from the 48V phantom power (inspired by a circuit diagram of the AKG C414).
I've built the circuit on standard matrix board with components on the top and the bottom to use all available space.
Finally, here's the modified supply module with the ME88 screwed on it:
