Shure 578 Omnidyne Microphone

Dad Roadie

New member
Hi to All,
Has anyone in the forum ever Taken one of these microphones apart? I need to replace a cable that gotten stiff because of age. Shure wasn't any help .They said it was to old. There is a cap on the end where the cable goes in .I'm not sure if it unscrews or just pops out. I don,t want to damage the microphone ,Its in really nice shape Any Help would be appreciated!
All the Best!
Dad Roadie
 
Have you tried removing the two screws adjacent to the switch to see if they also retain the end cap? I'd just loosen them a bit first and not remove them altogether to see if the end cap can be able to be moved. If it does have some give maybe then remove the screws all the way. If not, the cap might unscrew, but you don't want to use pliers that might nick it up.
I did have one old mic (not a Shure) that the body and top were glued together with something like a contact cement.
 
View attachment 98016Thanks for the reply . The screws didn't seem to help but the microphone is pretty old and the cap could be stuck I have put a copy of the instruction sheet if it might help.
All the Best!
Dad roadie
 
Yeah, I had grabbed that pdf, but unfortunately doesn't lend an idea how to disassemble.
Below are a couple old dynamic mic bodies I had in a parts drawer. No idea of the brand (think the longer one may be a Lafayette Radio). You can see one where the head was kinda glued to the body. The other one does have an end cap that screws in and the cap has flats to get a wrench on to, which I don't believe yours has. This doesn't really help you specifically for your Shure, but gives an idea what was done on some mics.
 

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Attached is a picture of the 578 that shows the cord area and the bottom a little better. Any ideals would really be great. I don't want to damage the microphone. As I mentioned the mic works great .The cord has gotten so stiff that its difficult to use.
Dad RoadieView attachment 98022
 
I did some searching and found an image of the backside of the cap. There are two dimples that are made for what's called a 'spanner wrench' (image below) that grabs those dimples to unscrew it. If you have a pair of needle nose pliers and if the cap isn't overly tight, you might be able to get it off using the pliers tips in the dimples. Be careful not to slip and poke yourself with the pliers (I know this :) )

578.jpg
image_17531.jpg
 
Arcaxis,
Thanks for the answer! I'm going down and try it first thing in the morning. Learn a long time ago never mess with something when your beat.
Dad Roadie
 
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