Shure 545 4 pin to 3 pin XLR conversion

Hi, LorenWith the 4-pin connector, all signals were present on different pins, so all that was requried to select impedance was to use the correct cable. A 4-pin to XLR cable was for low impedance; a 4-pin to 1/4" connector was for high imepdance. It wasn't neccesary to remove the mic's connector as it is on the modern model 545SD. The newer XLR connectors are not compatible I'm afraid - you'll notice that your mic has a screw-on retaining ring for the cable's connector to mate to - newer XLR connectors rely on a spring-loaded latch instead. 

These cables DO come up on eBay fairly often (I probably have some used ones myself) - and I have seen 4-pin to XLR adapters but I don't have any of those. If you are handy with a soldering iron then you can get any 4-pin connector cable and configure the cable how you want it. If my memory is correct, pins 1 and 2 are the high-Z pair and pins 3 and 4 are the low-Z pair. But it is easy enough to determine that by removing the connector from the mic. The white and black wires ARE the high imepdance pair (plus an additional black wire which is internal ground); the red and blue wires are the low impedance pair. I hope that helps but if that didn't answer your question feel free to ask again - here or by email - greg@blowsmeaway.com

Cheers!

Hey, LorenI don't know what the odds are, but one of the 545's I just bought came with a pigtail adapter - 4-pin to XLR male, st up ready to plug into a low-Z XLR cable. 

Yours for $12 plus shipping if you want it. (If you do contact me by email, tell me where you live so I can figure shipping and I will send you a PayPal invoice. )