Newbish Question Number 64: Phantom power

[alexis]

Hi - Someone suggested that if I preferred to use my "stand-alone" preamp to amplify a condenser mic rather than the preamp built into a hard disk recorder, I could run the stand-alone preamp into the hard disk recorder's audio in, but leave the phantom power off on the hard disk recorder. (Obviously, phantom power would be "on" in my stand-alone preamp).

Would that work transparently, or would the signal unavoidably be "colored" by the hard disk preamp, even if it had the phantom power turned off?

Thanks!

[Daniel Davis]

The signal would still go through both the stand-alone preamp and the hard disk recorder's preamp and be "coloured" by both. The phantom power button is not an on/off button for the preamp, and is a complete red herring.

[molecular]

Does your recorder not have a straightforward line in that you could plug the external preamp into?

[James Perrett]

It would also be better to plug the external preamp into your hard disk recorder's insert point return if it has them.

[Hugh Robjohns]

Hi - Someone suggested that if I preferred to use my "stand-alone" preamp to amplify a condenser mic rather than the preamp built into a hard disk recorder, I could run the stand-alone preamp into the hard disk recorder's audio in, but leave the phantom power off on the hard disk recorder. (Obviously, phantom power would be "on" in my stand-alone preamp).

Yes. The mic needs to receive phantom power from the preamp it is plugged into.

However, the output of your preamp will be line level, and you don't want to plug that into another mic-level input because (a) you will probably overload it and (b) most devices don't like phantom-power being fed into their line outputs! The preamp output should be connected instead into a dedicated line-level input or, failing that, using a Y-cable into the return side of a channel insert point.

Would that work transparently, or would the signal unavoidably be "colored" by the hard disk preamp, even if it had the phantom power turned off?

Passing the signal through two preamps is likely to add unwanted colouration as well as suffer problems with overload, and I wouldn't recommend it. And if phantom was turned on it could damage the external preamp output stage too.

H

[alexis]

Thank you molecular, James Perrett, and Hugh!

"Line in" from my preamp it is then!