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It's NOT phantom power! It's BIAS power!

SvenGolly
Apprentice

People keep using the term "phantom power" incorrectly when referring to a microphone with an external battery or needing low power from the source. The correct terms for just about anything using a 1/8" (3.5mm) jack (TRS or TRRS) are "BIAS POWER" or "BIAS VOLTAGE" or "PLUG-IN POWER". These small electret condensers need somewhere between 1.5 - 5 VDC at very low amperage as "bias power" for correct operation. This is the sort of power expected by USB mics, computer mics and external cell phone mics. (Canon Vixia camcorders do not supply any voltage on the mic input jack.)

 

"Phantom Power" is a generally agreed audio term (and DIN spec) meaning 12 to 48 VDC. That level of voltage is applied either through external power supplies or from a mixing board and it's generally through an XLR plug. The amperage is higher and the way the voltage is applied (and its purpose) is completely different from bias power.

 

Mixing the two terms could lead you to disaster. 

 

So what works in a Vixia? Anything with it's own external built-in bias voltage supply (most use LR44 watch batteries or AAA batteries) OR you can use a dynamic mic that doesn't require power (Audio Technica makes a few) OR you can use a professional mic with an external phantom power supply but that's likely to need an XLR to 3.5mm adapter which adds an unneeded extra gizmo. You can also buy external 3 - 5v power supplies for bias voltage but they are expensive (often more than the mic) AND you have to match the power supply to your mic since standards for bias voltage vary. Rode makes external adapters for their mics..

 

616SYw5nBIL._AC_SL1500_[1].jpg Here's a lav mic with an inline BIAS battery supply. Note that it has a switch for camcorders vs smartphones. That's because most phones supply the bias voltage themselves so the battery is taken out of the circuit in the OFF position.

 

Hope this helps and wasn't too annoying. 

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