Pooh Bear wrote:

Richard Freeman wrote:

"Pooh Bear" wrote in message
...
Bob Olhsson wrote:

In article , Fletcher
wrote:

This is true in most cases...

My understanding is that the problems arise with mikes having a
grounded center tap on their output transformer. Other problems are
hot-plugging mikes with the power on or using a microphone patch bay
that has phantom power running through it.

Yup, it's the centre tap that screws it up for sure.

Hot-plugging prolly explained a few mic I/P failures on Studiomaster
desks prior to me - lol. A few diodes to the supply rails fix that.

Yep seen plenty of blown diodes to the Supply rails from SC mic cables to

Ouch !

We fit a current limiting resistor now too. Should stop that.


Graham

I am a bit confused here. First I haven't heard of a mic with a centre
tapped transformer for many many years and second, all phantom power
supplies feed thru series resistors anyway and adding any extra ones may
reduce the voltage seen by phantom powered mics.

Ian