I have audio card with Hi-Fi input, but it is strictly stereo TRS (not balanced).
I have condenser microphone with balanced TRS output.
I found that mic output is very low, and I receive too much noize from its shield.
I need to connect microphone with galvanic isolation to drop all noize, so it should have absolutly clean zero level. I know it is capable of at least 50 dB of SNR, but now only 15 dB.
I opened mic, everything looks good, it is supplied with small (passive) powering scheme inside, involving few small transistors.
Ok, I have done some research and came to conclusion, I just used condenser mic without any power supply (hehe).
After some considerations I came up with this scheme.
Am I right to not connect shield from everything to GROUND/MIC_IN of sound card?
I will probably use batteries to achieve perfect noize-free environment.
Any recommendations on using capacitors before amplifier?