If you need a battery T microphone power unit that you can make see i7A
To make a battery phantom power unit see i7B

Ref: i7

Phasing A Microphone

If your microphones are out of phase, you will get a cancellation at the low end when the microphones are close together

When you buy a new or used microphone don't forget to check the phasing with your other microphones. In the past Sennheiser supplied 2 new MKH416 microphones to me that were out of phase. This can give you confusing problems when you are working with 2 or more microphones

You can check the phase of microphones by humming into the 2 microphones.

In a mono mode, when you bring up the level of the second mic to meet the first, the signal will add if in phase, but if there is a dip in the level when the levels meet, it is out of phase.

If you are checking a Miniature Electret with a Shotgun mic put the Electret by the capsule not at the end. Note : The capsule on a shotgun or rifle is situated just before the side vents.

To Change The Phase

Miniature Electret Lavaliere Microphones with plugs fitted for Radio Microphones will need the plug reconnected

You can change the phase of a Dynamic or a Phantom Powered Condenser Microphone at the 3 pin XLR by reversing the connections on pins 2 and 3. If you have either microphone you need to work out whether it is better to change the microphone or the Recorder or Mixer

To Change The Phase of a T Powered Microphone Or If It Is Not Working

On all T powered Microphones reversing the connections on pins 2 and 3 of the XLR, the microphone will either work or not work. With the microphone connected with a one to one lead, plugged into the recorder or mixer, if it works but it is out of phase you will have to send the microphone to me to change the phase at the capsule end.

If it is not working, reverse the connections of pins 2 and 3 on one end of a microphone cable and test it again. Or use a phase reversing adapter. If it is still not working you can send it to me for repair and if possible a good microphone to phase it to.

If using an AKB type battery 12 volt powering unit, if not working, just revers pins 2 & 3 the the XLR plug that connects to the microphone, if working but out of phase just revers pins 2 & 3 the the XLR plug that connects to the recorder

It is always better to have all your microphones adjusted to the same phase. Then have phase or power reversing adapters or different pigtail leads for different microphones. Or when the pressure is on you will always end up with egg on your face.

You can use a T powered microphone on a phantom powered microphone input, by using a 48p to T phantom to T power adapter, like UMA30 in the Used Microphones section. But you may have to change the connections over to pin 2 & 3 in the microphone side of the adapter if the microphone will not work.

Note: When recording, on all recorders, you need to check that microphone inputs you are not using are turned down and are not switched to "T". This is for powered microphone, when no microphone are plugged in that input, as the high gain preamp will pick up a hiss or time code and break through onto the recording.

Good luck! Mike

  For more ideas or suggestions contact us at Mike Harris Sound Services