NO POWER, NO INDICATORS, NADA -
Probably something to do with AC
power. Is it plugged in? Murphy’s Law. Check the fuse on the back panel. A blown
fuse often looks blackened inside or the little wire inside looks broken. A very
blackened fuse is a big hint that a short occured. Try replacing the fuse with a good
one of the same value and size. If it blows too then prepare to send the unit back to
the dealer or factory for repair. The fuse is a protection device and it should blow if
there is a problem. If the unit works with a new fuse, fine.
LIGHTS BUT NO SOUND -
This typically indicates a cabling problem. Check
to ensure the XLR mic cables you are using are not damaged. If the XLR and
micpreamp (and the rest of the signal path) are known to be good, it may be the mic.
LEVELS SEEM TO BE WRONG, NO BOTTOM -
Most likely one of two
scenarios. One, a partially broken cable. You would then be missing half the bal-
anced signal, and levels would be down approximately -6dB. Second possibility,
the signal’s polarity has been reversed somewhere. Try flipping the phase on your
micpreamp (if it has a phase switch), and see if that helps.
**Put on some headphones, close your eyes, and speak into the mic from a distance
of about one foot. Your voice should be full and clear with a solid low-end. With the
phase reversed, this solidity goes away and your voice will sound like it is swim-
ming all around your head with no clearly defined center image.**
HUM -
This is most likely a ground loop. Try a 3-pin to 2-pin AC adaptor (about
a dollar at a hardware store). We do not recommend breaking off the power cable’s
grounding pin.
BUZZ -
This is most likely a faulty ground somewhere in the chain. Make sure all
the philips screws holding the mic body to the mic base are tight. Stereo models or
older models might have loose set-screws that hold and ground the connectors to the
body system. Use a 1/16” hex key to tighten these set screws around the base of the
microphone. It might also be the tube making a bad noise - read on...
EXCESS NOISE, DISTORTION, SNAPS CRACKLES & POPS -
Probably a
tube. Luckily for you, they are very easy to change:
1. Turn the power supply off, disconnect it from the wall, and disconnect the
6-pin cable from the microphone.
2. Using a philips screwdriver, remove the two philips screws on the mic body
that hold it to the base of the microphone.
3. Gently, gently pull the base of the mic out from inside the body. The guts of
the mic will come out with it.
4. When you’ve pulled the insides all the way out (
be VERY careful not to touch
the delicate capsule!
), you’ll clearly see the tube. (hint: it’s the glass bottle with
some metal and no air inside it.)
5. Gently grasp the tube between your thumb and forefingers, and wiggle it out
of the socket.
6. Taking care to align the pins properly, insert the new tube into the socket,
and repeat these steps (again, CAREFULLY) to return the guts to the inside of
the mic. Make sure to properly tighten the screws at the base for a good chassis
ground connection!
For additional information, contact our Service Department:
www.manley.com/service.php
TROUBLESHOOTING
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