Posted by Richard Crowley on 08/28/07 16:44

"Rick Merrill" wrote ...
> There is one more tiny thing: the feed is Mono while the camcorder is
> Stereo. Right now we have both L and R inputs wired together in the
> stereo jack from the Mono feed. Suppose I put the L and R Mic In in
> series?

Perhaps you meant to put them in parallel. You can't
put them in "series". Feeding a mono signal into both
channels is a very common practice. Sometimes we
feed the house mix into one channel and a live mic
into the other channel. That gives you independent
redundancy, and the POV of the live audience. In some
cases (such as rock music performances), the direct
feed from the PA system is too "dry" and doesn't include
the non-amplified instruments, or the audience reaction,
etc.

> That would increase the Mic in impedance by 4x.

Putting two impedances in series increases the total
impedance by 2x, and putting them in parallel makes
the total 1/2 the individual impedances. But you can't
put the mic inputs in "series" unless you use a pair of
isolation transformers, etc.

Padding the mixer line-level output down to mic level
should not be dependent on the input impedance of
the camcorder. So impedance is a very minor factor
in your situation as you have explained it here.

> Would that be a step in the right direction?

Padding the line level down to mic level would be the
right direction. Using shielded cable would definitely
be the right direction.

You could even consider recording the audio on some
other machine (that doesn't have AGC), but we don't
know what your production flow is and whether you
could accomodate separete sound recording? And
we don't even know what you are producing and how
much of a problem the "pumping" is?

[Back to original message]