7 pin Tube Mic Cable wiring question

[jackinthebox]

I have a question regarding wiring for 7 pin tube mic cable. specifically GAC-7.

According to Klaus Heyne the neumann protocol for tube mic wiring is:

conductor 1. white audio +
2. black audio -
3 and 7 thick blue and shield.(ground)
4. thick red heater.
5. yellow 120volts
6. green 0-120volts
and the 7th grey conductor is cut short and isolated.

My question is, are there different protocols for different microphone manufacturers? I have a microphone in front of me where the pins 4 and 7 are the ground/shield and pin 3 appears to be the heater voltage, but it is otherwise the same as the configuration described by Klaus.
Will it damage the mic if the wrong wiring is used?
It appears to work fine and give a great sonic improvement when i use Gotham GAC-7 with the Neumann configuration but i'm guessing the grounding will be all wrong? Or is it just connecting the heater filament in reverse and still grounding but via a different route?
Any advice gratefully recieved.

thanks in advance

jack

[theBF]

I have started making cables for customers with this cable and Neutrik connectors. Its very nice.

It has two heavier wires to provide a high current path for the filament power for the tube. I created my own color code using the way the wire is organized to decide which wire goes to what pin. That keeps the stress on the wires low and makes assembly easier.

The exception is that I use the blue heavy conductor for ground and the Red heavy conductor for the filament 6.6 volts.

The cable does not seem to have a distinct audio pair so I picked two conductors that were close together for best common mode rejection.

Hope that helps.

BF

[jackinthebox]

Thanks for the reply. That's what I've ended up doing. It does appear however that each mic manufacturer might have a different arrangement so it is worth checking inside the mic before making up cables.it's possible to send 120v directly to ground and the housing. Great cable though