Ray--
Your camcorder has manual gain. I suggest always using this feature
if you aren't already. I'd go the portable phantom supply route first
and do a high gain comparison test to see how bad or good the mic pre
in the camcorder is.
> >
>>AT4022's -> Rolls PB22 -> Mic Input M10 (max or near max gain)
>>vs
>AT4022's -> Rolls PB22 -> Mic Input HS700's (max or near max gain)
I personally would not start off introducing the M10 into the record
chain because even if it has lower noise, when you connect it to
camcorders mic pre, the noise performance will be limited by the last
device. Driving the camcorder's mic input with a hot signal will
lower headroom considerable and make setting gain in the field very
tricky. Rob D.
Good luck with the test, let us know if you need help doing it. Rob D.
=3D =3D =3D
=3D =3D =3D
At 12:40 AM -0400 7/21/10, Mitch Hill wrote:
>
>
>At 10:41 PM 7/20/2010 -0500, Rob wrote:
>
>>Opps, I forgot to mention that if the HS700's mic input only has
>>auto-gain, the recordings will "pump" and this makes nature
>>soundscapes sound pretty bad. If it turns out the HS700's mic input
>>is noisy or it only has auto-gain, looks like you're stuck with using
>>another sound recorder.
>
>I think this is Ray's original plan as he has a PCM M10 and his original
>question was, "How (or can) I use my Sony PCM-M10 with my Panasonic
>HDC-HS700 camcorder for better sound quality and if so how? I'd like to be
>able to walk around and record with this configuration."...
>
>However, making a "T" type resistor network to pad down the audio, the
>output of the M10 can be made low enough to get under the threshold of
>level that causes pumping in the video camera. Whether or not there will b=
e
>enough gain at that point is another issue however using the PCM-M10 ahead
>of the mic input of the video camera allows for control of the mic preamp
>gain at the input of the M10 recorder thus controlling the level of the
>output going to the video camera. The "T" network is a fixed ratio device,
>it will only reflect the level of PCM-10 output at whatever the reduction
>established by the value of resistors used. It doesn't necessarily have to
>be 40 dB, it can be what ever the ratio of resistor values chosen makes it=
.
>Then the PCM-M10 becomes the controlling device.
>
>As most all cameras are AGC, Auto Gain Control, you may have to experiment
>with the value of the resistors chosen to find the values that work best
>with your camera however they resistors are inexpensive, usually between
>$.05 to $.20 cents. And if you need more control range, one of the
>resistors in the "T" network can be a variable resistor or
>potentiometer...
>
>>If the HS700 does have _manual_ audio gain, one way to test/compare
>>recorder input noise is to make comparison sound recording in the
>>same, quiet location with these two record chains:
> >
>>AT4022's -> RollsPB22 -> Mic Input M10 (max or near max gain)
>>vs
> >AT4022's -> RollsPB22 -> Mic Input HS700's (max or near max gain)
>
>I agree with Rob's test, this will give you an idea of what is the best
>direction to take wether the camera has manual gain or not. You may find
>the simple fix is to use the AT4022 mics with a Rolls PB224 phantom power
>module on the video camera itself. That is assuming the video camera
>itself uses an audio digitizer with adequate rate.
>
>Another potential gotcha about cameras that I learned recently, if using
>the internal camera microphone, its liable to be a monaural mic and the
>digitizer runs at a low rate around 11Khz. However, when a microphone
>plug is inserted into the camera external microphone input jack, the camer=
a
>switches to a digitizing rate of 44.1Khz and generates excellent audio
>recordings...
>
>--
>
>Thanks,
>Mitch & Shadow...
>
><http://www.4shared.com/dir/UTASxktL/wildlife.html>http://www.4shared.com/=
dir/UTASxktL/wildlife.html
>
>Shadow's area:
><http://www.4shared.com/dir/ecfWjyZb/Shadow.html>http://www.4shared.com/di=
r/ecfWjyZb/Shadow.html
>
>
>
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