Phantom power supply? External mic preamp? Plug-in power?

[raphb]

Hi guys,

Trying to understand how to get the best audio here and some questions popped up..

What is the difference between the concept of plug-in power and phantom power besides the change in voltage that is supplied? Is there a difference?

Does a microphone (NTG-2, MKE 600) that supplies its own battery use zero electricity from the recorder/preamp, i.e. no phantom power and no plug-in power? Does this reduce the drain on the recorder battery?

Would a phantom power supply (Sony XLR-1 or Rolls PB224) reduce load on the preamp in a recorder and reduce the hiss? How do they compare to a Juicedlink/Beachtek device?

Regards
-Raphael

 

[Richard Crowley]

What is the difference between the concept of plug-in power and phantom power besides the change in voltage that is supplied? Is there a difference?

The concept is the same. Only the implementation is different. In addition to "P48" (and P24 abd P12) "Phantom Power" (IEC 61938) there is also "T-Power" (DIN 45595) which is vaguely half-way between P48 and "plug-in power"
For a good overview see: http://en.wikipedia.org/wiki/Phantom_power

Does a microphone (NTG-2, MKE 600) that supplies its own battery use zero electricity from the recorder/preamp, i.e. no phantom power and no plug-in power? Does this reduce the drain on the recorder battery?

Correct and Correct.

Would a phantom power supply ... reduce load on the preamp in a recorder

Very likely.

and reduce the hiss?

No. Phantom power (and how it is provided) has almost nothing to do with signal-to-noise ratio ("hiss").

How do they compare to a Juicedlink/Beachtek device?

Compare how?

 

[TheDingo]

Would a phantom power supply reduce load on the preamp in a recorder and reduce the hiss?

Phantom power has nothing to do with pre-amp performance, but some mics like the NTG-2 and the MKE600 produce a stronger signal when running from external phantom power compared to running off an internal AA battery. So you may get reduced hiss from the stronger signal produced by the phantom powered mic.

In terms of recorded sound, the quality of your mic, the placement of your mic, the quality of your pre-amp/mixer, the quality of your recording device, the skill of the audio operator, all together will determine how good your final audio recording will be.

 

[John Willett]

Phantom Power
Puts the +ve voltage along both legs of the balanced cable (so it is invisible to the audio - hence the term "phantom") with the -ve using the screen. Phantom power is only used on balanced microphones. Phantom is normally 48V +4V, though 24V and 12V are also in the standard, but not so common - hence some microphones being 12-48V compatible. 48V phantom power is the international standard for studio microphones.

T-Power (sometimes called AB Power)
Also used with balanced microphones only. This is 12V and the +ve voltage uses the +ve audio line and the -ve voltage uses the -ve audio line - the screen is not used at all for the power voltage. There are blocking capacitors in the microphone and in the power supply to prevent the power getting into the audio chain. This was really invented for portable recorders in the days where you could not get 48V from batteries without using large and heavy batteries. T-power used to be the standard for location recording microphones, but is dying out as a standard as you can now get small DC/DC converters built into the portable equipment to give phantom power.

Plug-in Power
This is a low voltage supply used for unbalanced electret microphones (ie: tie microphones and inexpensive consumer microphones). Normally about 4 - 9V, it works in a similar way to T-Power with the +ve voltage using the +ve audio line, but the -ve voltage uses the screen (as the mic. is unbalanced). There is a problem in that some American companies try and call this "phantom power" which is very confusing and misleading as "plug-in power" is very different and non-compatible with "phantom power".

All these powering methods are non-compatible and are very different from each other and it's possible to damage a microphone if you use the wrong one.

I hope this helps.

 

[raphb]

Thanks guys. That was great. For some reason I didn't think about looking at Wikipedia for Phantom Power, I'll check that out.

 

[Rick R]

As John stated, many electret mics (hard-wired lavalieres for instance) include a Phantom Power 'adapter'. The wording the manufacturers use, insinuates it's a 'true condenser' mic.. which it ain't.. (for what that's worth)