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Re: inverting a track on a stereo recording to increase gain....huh?

Subject: Re: inverting a track on a stereo recording to increase gain....huh?
From: "Flawn Williams" flawn1951
Date: Sat May 4, 2013 5:21 am ((PDT))
What is likely happening here is that you are sending a balanced mono signa=
l from your mono mike into the LS11's input. But that input is expecting a =
stereo unbalanced input.

In a balanced circuit, the audio is identical on both signal wires, except =
that whenever the voltage on one wire is positive, the other is negative, a=
nd vice versa. Mix them together, they cancel out.

But invert the polarity of one side or the other after recording, and now t=
hey add to each other.

Actually, you probably don't need to go as far as you did in inverting the =
polarity and making a new stereo track. Just split the stereo track and use=
 either resulting mono track by itself. You'll probably have plenty of volu=
me.

Want to know more about balanced circuits? Wikipedia has a primer.

http://en.wikipedia.org/wiki/Balanced_circuit

--Flawn





On May 4, 2013, at 5:21 AM,  wrote:

>  inverting a track on a stereo recording to increase gain....huh???
>    Posted by: "Chris Harrison"  lamprophis1963
>    Date: Fri May 3, 2013 1:09 pm ((PDT))
>
> OK,
>
>
>
> I'm a novice at this and all my formal training is in biology, not
> engineering or electronics.  I did take physics as an undergrad, but I th=
ink
> my professor was Isaac Newton. ;-)
>
>
>
> I have been making some frog recordings with a Sennheiser K6/ME66 shotgun
> into a LS-11 recorder.  I recently purchased a 90 elbow microphone plug
> extension for the recorder to stop me from bending plugs.
>
>
>
> Recently a new problem has arisen.  When I import the recordings into
> Audacity, I can't get the gain up high enough even though there is plenty=
 of
> gain in the recording as far as I can tell.
>
>
>
> Doing a little research on the internet, I saw a suggestion to split the
> stereo track, invert one of the two resulting tracks, then recombine the =
two
> tracks back into a new stereo track.   Surprisingly (to me) this works li=
ke
> a charm.  I now have plenty of gain.
>
>
>
> I have no idea what "inverting" the right channel does, or why this works=
,
> and might not understand if you explained it to me.  But what can I do to
> avoid having to do this?
>
>
>
> If I record directly off the LS-11 built in mics, I have no such problem.
>
>
>
> Any gentle input?
>
>
>
> Chris Harrison
>
> San Antonio, TX
>







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