Apparent Vintage Shure 545 Transformer Issue

[Janalex]

Hey all,

I've been trying to find any online references to Shure mic transformers failing and have not been successful. I can't imagine at this low voltage windings shorting but I can't explain what I'm seeing any other way. I removed the capsule and tested it without transformer and its working. Don't seem to have any continuity issues on the capsule side (yellow/green/black). However I am getting a short beep on the DMM when touching black ground and white (which I removed from pin 3). The XLR male connector is removed. I do not get this beep on an SM57 I have. Mic sounds thin with no low end. I am assuming next step would be to remove the transformer. Can someone recommend safest way to do so and what to look for after removal? Any similar stories?

Jan

 

[Walrus]

The white wire of the 545 transformer is the high impedance output and is unbalanced, therefore there will be a continuity between the black/case/pin 1 and white wire.
The SM57 is only low impedance balanced output, with a choice of 50 or 150 Ohms.
The usual cause of a thin sound is damage to the diaphragm, or the diaphragm has come unstuck.

 

[Chandra]

All these mics can work without a transformer. The only issue is when plugging in to a deck with 48 volts DC already turned on.
Regards.

 

[Chandra]

A youtube video showing how the transformer is removed and connected direct.

Regards.