I do no have a M147 and I have not looked at one. I like to look at schematics and figure out what is going on like people do puzzles
Looking at a schematic you can find on the web for the M147 I noticed it uses a what looks like it might be an impedance balanced output.
If you look the + side output resistance before C11 is 95.3 ohms / 2.
I do like the parallel opamp output and use of 32VDC. I like the 40Hz HPF filter selection. Clever use of a resistive voltage divider for the pad in the follower emitter leg.
The - is connected to ground unlike other impedance balanced microphones that would have a another matching resistance( 95.3 ohms / 2 in this case) with a cap to ground
The output does appear across R17 and then a filter network.
Is there anything in the power supply enclosure that connects to the + and/or -output except a connection to the 3 pin XLR? I have not found a picture of the inside of the power supply on the web.
I am a puzzled by this output stage with the - to ground unless this is going into a high impedance input preamp(transformer or a high impedance semiconductor circuit )
The CMRR will be degraded by the impedance not be low and the same, unless I am misunderstanding CMRR.
The 22uF is about 1/2 of 47uf. Two 47uf in series
Looking at a schematic you can find on the web for the M147 I noticed it uses a what looks like it might be an impedance balanced output.
If you look the + side output resistance before C11 is 95.3 ohms / 2.
I do like the parallel opamp output and use of 32VDC. I like the 40Hz HPF filter selection. Clever use of a resistive voltage divider for the pad in the follower emitter leg.
The - is connected to ground unlike other impedance balanced microphones that would have a another matching resistance( 95.3 ohms / 2 in this case) with a cap to ground
The output does appear across R17 and then a filter network.
Is there anything in the power supply enclosure that connects to the + and/or -output except a connection to the 3 pin XLR? I have not found a picture of the inside of the power supply on the web.
I am a puzzled by this output stage with the - to ground unless this is going into a high impedance input preamp(transformer or a high impedance semiconductor circuit )
The CMRR will be degraded by the impedance not be low and the same, unless I am misunderstanding CMRR.
The 22uF is about 1/2 of 47uf. Two 47uf in series