Posted by: "scottsherk27"
> How does one do this? Just putting a meter across the pins doesn't
> seem to be telling me anything.
Make sure you use a DC meter that's not loading the system significantly
or you won't get a true reading. Then check the voltage on each leg at
the XLR going into the mic. Check the DC voltage between pin 1 & 2, and
between pin 1 & 3. That's the working phantom power voltage the mic sees
when running. If these two voltages don't match, turn the power off,
disconnect the mic and check the resistance between the same two pairs
on the power supply side. That should be matched within better than 1%
at 6.81 k-ohms. Any mismatch on the two load resistors in the power
supply will allow some leakage of whatever noise is in the power supply
lines. It's by supplying the exact same voltage to both sides of the
signal (pins 2 & 3) any noise in the power supply is canceled.
I know that a measured voltage of 36 volts will allow the MKH to produce
a signal that sounds normal. Sennheiser says it should be above 44 volts.
Walt
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