Yes, all plug in power inputs are unbalanced.
A phantom power input is somewhat different, as it is balanced. Both pin 2
and 3 have +48 v, which means that there is no current flowing through the
coil. (The coil is connected to pins 2 and 3)
That is why the 6,81k resistors should be matched. If unequal, a current
will flow.
Klas.
At 00:25 2006-04-24, you wrote:
>This seems to be a different take on phantom power potentially
>damaging dynamic mics (from the Shure site):
>
>
>---quote---
>
>Question:
>
>"I have an eight channel mixer which sends phantom power to all
>mic inputs when the phantom is activated. I would like to run a
>Shure SM81 and a Shure SM58 through this mixer in a live
>performance situation. My question is if I enable the phantom
>power on the mixer for the SM81, will it affect the operation of
>the SM58?"
>
>Solution Database Answer:
>
>No. Any Shure dynamic microphone with a low-impedance balanced
>output, like the SM58, is not affected by phantom power. Phantom
>power will not damage a professional dynamic microphone.
>
>---endquote---
>
>
>I assume Plug-in-Power, being much lower voltage (and current?)
>than Phantom, would be even less likely to cause harm.
>
>I should think that a DC voltage across the coil in a dynamic
>would, if it is allowed in, tend to bias the diaphragm and
>reduce sensitivity. Whether that would cause residual magnetic
>charge or not, I couldn't guess. But the Shure answer refers to
>"professional" dynamic mics, so maybe they're hedging on
>unbalanced and/or el cheapo designs.
>
>Klas, were you assuming an unbalanced input?
>
>Also, I couldn't quite reconcile your two replies...
>
>
>Allen Cobb
>http://timbreproductions.com
>
>
>-----Original Message-----
>From:
> Behalf Of Klas
>Strandberg
>Sent: Saturday, April 22, 2006 7:13 PM
>To:
>Subject: Re: [Nature Recordists] PIP.
>
>
>You should not connect a dynamic microphone, or a microphone
>with an output
>transformer. Both might get magnetized.
>
>Klas.
>
>Depends on how the microphone in question is made, but it
>shouldn't have
>any effects.
>The plug in power is too low to blow a wrong polarized output
>condensor.
>The question is more what happens inside the plug in power
>pre-amp, when
>the current regulator is idling, without load.
>
>Klas.
>
>
>
>
>
>"Microphones are not ears,
>Loudspeakers are not birds,
>A listening room is not nature."
>Klas Strandberg
>Yahoo! Groups Links
>
>
>
>
Telinga Microphones, Botarbo,
S-748 96 Tobo, Sweden.
Phone & fax int + 295 310 01
email:
website: www.telinga.com
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