On Mon, 14 May 2001 13:13:21 GMT, Kyle
>Didn't have much time to play this weekend because it was mother's day
>weekend and all the family stuff and yada yada yada, but we did break
>out the camera a bit on Satuday afternoon.
>
>Test Bank 1
>
> (soft volume) (loud volume)
>
>receiver level 5 8 10
>VX manual level -20 -20 -20 db
>
>receiver level 5 8 10
>VX manual level -12 -12 -12 db
>
>receiver level 5 8 10
>VX manual level 0 0 0 db
>
>
>Test Bank 2
>
>receiver level 5 8 10
>VX level auto
>
>
>6-10 seconds of audio were recorded to tape for each combination of
>levels. What I was interested in was the overall loudness of the
>recorded audio in proportion to hiss, because the past 2 times (and only
>2 times) we've used the wireless with the VX, the audio has been very
>soft. This has not been the case when we've hooked it up to our GL1's.
>Apparently the GL1 is not as fickle when it comes to audio. We set the
>receiver volume to 5 out of 10 and it records perfectly.
>
>With the receiver on 10 and the VX manual level at 0, the signal was
>still weak. By weak I mean, in order to hear the sound when I played
>back the tape on TV, I had to turn the volume up 3/4 of the way before I
>could hear anything being said.
>
>I have not captured the footage yet and played with it in premiere.
>Maybe I can do that tonight, but so far all I have really done is
>collected some initial samples.
I applaud your efforts, but have a few comments...
(I assume in the above that you are using a wireless
receiver with output level controls that you are
adjusting - though you do not say what the source is
that you are recording, and how constant-level it
is...). I would add the GL-1 to the mix, so that you
have a reference (to remove a couple of variables,
like transmitter condition having changed since you
switched to the VX-2000 [possibly indicated by your
comment on the only-recently low level of audio
captured - something outside the VX-2000 appears
possibly to have changed...]), even though the AGC
circuits of these two camera are VERY different,
and the AGC of the GL-1 is not defeatable (and would
at most times, due to the compression, give a higher
average output than the VX-2000 AGC, which has
less compression [and none, in manual mode...]).
Also, I would check to see that the "line/mic" level
switch on the VX-2000 is operating properly. If you
are recording "live" material, it must stay constant
in average level for a valid test. If all is working
properly, both in manual and in AGC, I would expect
the average sound level of the VX-2000 to be lower
(due to the reduced compression compared with the
GL-1), and therefore the relative noise floor to be
higher when external gain is adjusted for similar
volumn level (with the VX-2000 sound having higher
peak levels and lower "quiet" levels [limited by
the noise floor]), unless you have not matched the
receiver level well to the VX-2000 AGC input needs
(which is unusual, due to the low sensitivity of
the built-in mic compared with most others, which
can easily result in too high an average level and
excessive peak limiting with the VX-2000). You may
have gathered that such testing has many pitfalls.
Best is to make sure that the VX-2000 is operating
normally, that the gear external to the VX-2000
is operating normally, and that they are properly
matched in use. Then, with familiar audio material,
see if the results are satisfactory and/or within
the range of reasonable expectations... (if all else
were equal [they aren't...], and all gear properly
working and well-matched, with the lower AGC
compression on the VX-2000, I would expect a lower
average output level, and a resultant higher [but
still barely audible, even on a good sound system]
noise floor in return for greater dynamic range
in the recordings). It is best not to make
assumptions about gear condition and matching
without checking these as much as possible before
doing other tests...