Bought a shure sm7b and am having an issue I havent had with my other mics. The first time I hooked it up I wasnt getting a signal at all through my preamp. I switched the mic cable and then I was good to go. The next day I was tracking some vocals and every time I touched the mic cable the mic would pick up lots of crackling noises. So I switched to yet another cable and am having the same problem. If the cable gets barely touched the whole signal cracks in and out. I've also noticed whenever I touch the knobs on my preamp when it's receiving a signal from the sm7b, I hear lots of hum through my monitors, but it stops when I let go. Weird! Should I return the mic? I should note, I've never had an issue with any of these mic cables before. And I've used them on other mics since I've gotten the sm7b and they work just fine.
Is something wrong with my sm7b?
- Thread starter Kerfoot32
- Start date
Steenamaroo
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Did you buy the Sm7b brand new?
Since you're getting varying symptoms across cables, and the cables are known to work with other mics, I'm inclined to think the mic is the problem.
The SM7B is incredibly solid. Do the pins on yours happen to feel loose at all? The cables should have a nice satisfying fit into the Shure mic barrel. Is that the case?
I'm going to get mine now to see how easy it is to remove the XLR connector.
I'm betting you've got a loose wire in there.
Since you're getting varying symptoms across cables, and the cables are known to work with other mics, I'm inclined to think the mic is the problem.
The SM7B is incredibly solid. Do the pins on yours happen to feel loose at all? The cables should have a nice satisfying fit into the Shure mic barrel. Is that the case?
I'm going to get mine now to see how easy it is to remove the XLR connector.
I'm betting you've got a loose wire in there.
Steenamaroo
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Plug an xlr cable into the microphone.
Turn the small XLR screw on the mic anticlockwise, Just turn it enough for clearance. Don't force it.
It's a reverse thread grub screw so it will disappear into the XLR barrel rather than coming out.
Now gently take out the cable. Do it slowly, and only pull out an inch or two.
The mic's XLR pins and wiring will come with.
Have a look to see if one of the wires is loose.
While there's suspicion I'd make sure phantom power doesn't get anywhere near it.
Turn the small XLR screw on the mic anticlockwise, Just turn it enough for clearance. Don't force it.
It's a reverse thread grub screw so it will disappear into the XLR barrel rather than coming out.
Now gently take out the cable. Do it slowly, and only pull out an inch or two.
The mic's XLR pins and wiring will come with.
Have a look to see if one of the wires is loose.
While there's suspicion I'd make sure phantom power doesn't get anywhere near it.
Last edited:
Steenamaroo
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Cool.
I'm aware of that.
Plenty of people have mixers or interfaces with grouped phantom.
If your hot or cold is disconnected phantom would probably damage the mic. Figured it was worth a mention.
The pre is a great river me-1nv inserted in a line input on my tascam us-1800 interface which plugs into my pc via usb. Both the pc and interface are plugged into a power strip which is plugged into the wall. My pre only does the hum thing with the sm7b. No issues like this have ever occured before. And they stop occuring when I'm not using the sm7b.
I'm aware of that but I make sure that is all turned off when I'm using dynamics.
David Cooke
New member
It definitely sounds like an open circuit somewhere in there based on what you've said. If its used I'd get my money back asap. And that preamp is too nice to be plugging a faulty mic into.