> If one however connects the balanced output of the ART Phantom II Pro to =
the single-ended input...
Raimund,
I own two AT3032, an Art Phantom II Pro and a Y cable XLR R+L to Jack 3,5 s=
tereo, so I'm able to connect Two AT3032 to a Sony M10 (or Olympus LS5) via=
ArtPhIIPro: can this be usefull to our test?
Regards.
Marco Pesente
--- In "Raimund" wrote:
>
> > I just measured the iRig Pre this morning as well. I got and EIN of
> > -112 dBu 20 Hz-20KHz unweighted (-114dBu A-weighted) with input
> > terminated at 150 ohms.
>
> Thanks for the confirmation, Rob!
>
> There is one thing that might explain the differences observed by Marco b=
etween the iRig PRE and the ART Phantom II Pro:
>
> The iRig PRE internally probably subtracts the two output signal rails (+=
and -) of the balanced microphone from each other and outputs the differen=
ce of both at its single-ended output. So, this is obvioulsy a perfect conv=
ersion from the balanced input to the unbalanced (single-ended) output.
>
> If one however connects the balanced output of the ART Phantom II Pro to =
the single-ended input of the SONY PCM-M10 through the XLR pins 1 and 2 onl=
y (leaving pin 3 open), then the output signal level (as seen by the single=
-ended input) will be reduced by 6 dB because the other rail is not being u=
sed. This would mean that the effective sensitivity of the microphone is ha=
lved (from 20 mV/Pa to 10mV/Pa), which would in turn increase the demands t=
o the preamp and may increase the overall system noise floor.
>
> For a mono recording setup, there would be a relatively simple way to imp=
rove the final signal-to noise ratio by about 3 dB:
>
> 1. Connect the balanced output of the phantom power box to the unbalanced=
stereo input as follows:
>
> XLR 1 <---> Sleeve
> XLR 2 <---> Ring
> XLR 3 <---> Tip
>
> This will record the positive output rail of the microphone to the right =
channel and the negative output rail to the left channel.
>
> 2. Subtract the recorded stereo tracks from each other, which will result=
in a mono track with doubled signal level for those signal components that=
are present in both tracks. Because the noise components of the both track=
s are not related to each other, the noise floor should only increase by 3 =
dB.
>
> Regards,
> Raimund
>
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