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Re: converting unbalanced signal to balanced and FR-2LE

Subject: Re: converting unbalanced signal to balanced and FR-2LE
From: "Philip Tyler" macmang4125
Date: Mon Feb 11, 2008 3:00 pm ((PST))
Glad it's sorted, happy recording!

Phil

--- Hector Centeno <> wrote:

> OK! Problem solved. It's the adapters (obviously). I
> found that pins 1
> and 3 were also in contact with the outer barrel of
> the XLR.
> Disassembling the adapter separating the 1/4 input
> section from the
> XLR output section made the noise to stop. Thanks a
> lot for your
> advice.
> 
> 
> Hector
> 
> 
> 
> On Feb 11, 2008 2:27 PM, Philip Tyler
> <> wrote:
> >
> >
> >
> >
> >
> >
> > Hi Hector
> >
> >  Just checking, you have turned the phantom power
> off
> >  have you on the FR2 LE? As that could cause
> problems.
> >
> >  Wiring the earth / screened to both pins 1 and 3
> >  should not cause problems, unless the input is
> not
> >  transformer balanced but electronically balanced.
> But
> >  I would have thought that the FR2 LE had
> transformers
> >  on its input.
> >
> >  I wire my unbalanced microphones the way I
> outlined
> >  and I have not had any problems.
> >
> >  If I am wiring up the balanced output of an
> >  electronically balanced unit to work into an
> >  unbalanced device then you only use pins 2 and 1
> >  leaving pin 3 floating.
> >
> >  Phil
> >
> >
> >
> >  --- Hector Centeno <> wrote:
> >
> >  > Hello,
> >  >
> >  > Thank you for your responses. Yes, I'm aware
> that
> >  > the 1/4 inputs in
> >  > the FR-2LE are line level so the first thing I
> did
> >  > was to use a 1/4
> >  > inch to XLR adapter to plug the AT-822 1/4
> outputs
> >  > (which basically
> >  > does what Phil suggested: hot to pin 2, ground
> to
> >  > pin 1 and 3) but to
> >  > my surprise I got a loud noise interference
> >  > (buzzings that seem to
> >  > come from the electronic circuits) mixed with
> the
> >  > audio signal. So
> >  > following this advice
> >  >
> http://www.dplay.com/dv/balance/balance.html#cross I
> >  > built a
> >  > 1/4-female to XLR-male cable soldering the hot
> (red)
> >  > wire to pin 2 and
> >  > the ground (white) to pin 3 leaving pin 1
> >  > disconnected. Now there is
> >  > no noise! But if I touch the connector on the
> 1/4
> >  > end (which is
> >  > metallic) I get a soft ground hum. Any
> suggestions?
> >  >
> >  > Cheers,
> >  >
> >  > Hector
> >  >
> >  >
> >  > On Feb 11, 2008 1:19 PM, oryoki2000
> >  > <> wrote:
> >  > >
> >  > >
> >  > >
> >  > >
> >  > >
> >  > >
> >  > > Hector,
> >  > >
> >  > > I think you'll have to convert your mic
> cables to
> >  > XLR, and not because
> >  > > of the balanced vs unbalanced signal issue.
> >  > >
> >  > > Page 42 of the FR-2LE manual describes the
> analog
> >  > inputs
> >  > >
> >  > > "These connectors are "combo" type (both 1/4"
> and
> >  > XLR) and can connect
> >  > > an external microphone via the XLR connector
> or
> >  > an external line level
> >  > > source via the 1/4" connector."
> >  > >
> >  > > On page 50, the manual says
> >  > >
> >  > > "The XLR connection accepts an analog signal
> >  > between -50 dBu and -10
> >  > > dBu...the phone plug accepts a -10 dBV analog
> >  > audio signal."
> >  > >
> >  > > -10 dBV is equivalent to -7.78 dBu
> >  > >
> >  > > This says to me that the 1/4" inputs won't
> work
> >  > well with a microphone
> >  > > unless the audio source is extremely loud
> (rock
> >  > band, plane taking
> >  > > off, huge crashing waves, etc.)
> >  > >
> >  > > To test this idea, I found an inexpensive
> Radio
> >  > Shack mic with 1/4"
> >  > > output in a drawer. I plugged it into my
> FR-2LE
> >  > and started
> >  > > recording. I had to talk in a very loud
> voice, a
> >  > shout almost, to
> >  > > register a signal.
> >  > >
> >  > > So the 1/4" input is probably not the right
> >  > choice if you're trying to
> >  > > capture a natural ambience. It might be just
> >  > right to record steam
> >  > > locomotives, however!
> >  > >
> >  > > --oryoki
> >  > >
> >  > >
> >  >
> >
> > 
>
> >  Sent from Yahoo! Mail - a smarter inbox
> http://uk.mail.yahoo.com
> >
> >  
> 



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