Can I change a Shure 14h (high imp) to a 14L (low imp) by rewiring as per the included diagram sheet or are they totally different units?
Bypass the output transformer of the 14H to make it a 14L. The directions below are for the model 14H:
1) On the mic element, remove the jumper between the center terminal and the terminal with the black wire.
2) Disconnect the green wire from XLR pin 1.
3) Disconnect the orange wire from XLR pin 3.
4) Disconnect the red wire from the transformer.
5) Connect the red wire to XLR pin 2
6) Disconnect the yellow wire from the switch.
7) Connect the yellow wire to the mic element center terminal.
8) Connect a new wire from XLR pin 3 to the switch terminal that has a black wire.