Octava MK-012 Microphone

[Pete Cofrancesco]

I have it mounted on my Sony Z1U and it works fine when wired into the camera, which supplies phantom power, but it won't work with my Audio Technica Wireless transmitter. I assume the reason is that the wireless transmitter doesn't provide phantom power.
Two questions:
1. Do any wireless transmitters provide phantom power?
2. Why does my Dynamic microphone that isn't battery powered can work without phantom power and works just fine with the wireless transmitter?

[Steve House]

Originally Posted by Pete Cofrancesco

I have it mounted on my Sony Z1U and it works fine when wired into the camera, which supplies phantom power, but it won't work with my Audio Technica Wireless transmitter. I assume the reason is that the wireless transmitter doesn't provide phantom power.
Two questions:
1. Do any wireless transmitters provide phantom power?
2. Why does my Dynamic microphone that isn't battery powered can work without phantom power and works just fine with the wireless transmitter?

Some plug-on trnsmitters provide phantom, others do not. The Sennheiser SKP100 doesn't but their SKP500 does, for example.

Dynamic mics and condensor mics use two entirely different principles of operation. The dynamic mic is a mini-generator. The vibration of the diaphram causes a coil to move in a magnetic field, generating an electric current in the process, which is sent straight to the recording preamplifier. It works just like a loudspeaker, only in reverse. Condensor mics rely on two charged plates moving with respect to each other changing the conductance of a circuit in some designs, modulating a superimposed AC current in others. This means there needs to be a source of electrical power to charge the plates and also to provide power to operate the internal pre-amp and impedence matching circuitry that makes it all go. Phantom power is one way of fulfilling this power requirement. Battery is another. T-power is yet another.

Phantom is a particular scheme used to provide the necessary voltage for a condensor mic over an XLR connection while making it invisible if you accidently connect a dynamic or ribbon mic to it. Ribbon mics are particularly susceptible to damage if you accidently put a voltage across their output terminals. Wireless transmitters usually provide sufficient power to operate a condensor lav mic attached to them but that "mic power" uses a totally different connection scheme and voltage from phantom. The bodypack transmitters provide about 5 volts mic power, sufficient for a typical lav, but that's quite different from 48v phantom.

[Pete Cofrancesco]

thx for the explanation. makes perfect sense now.