trouble with audio feed to camera

[frogfeet]

Hi folks, recently i did sound for a folk concert and had to provide a
feed to the video guy. The board they provided me with was
one of those Allen and Heath mix-units (the one with no assign buttons
over the faders). So I set up the house mix and gave the video guy
line outs from a couple of aux sends. He was telling me he needed more
signal so after almost maxing out the aux send levels I started
cranking the pre-amps, still not enough, and we were starting to hear
hiss in the video audio because the pres were so maxed out. We tried
switching audio input level sources on the camera and finally arrived
at a compromise we could live with.
So what is going on here? The video guy is telling me that broadcast
levels for inputing audio to the camera should be at +30 instead of my
line level of +4 from the board. Any help?

[George's Pro Sound Co.]

"frogfeet" > wrote in message
...
> Hi folks, recently i did sound for a folk concert and had to provide a
> feed to the video guy. The board they provided me with was
> one of those Allen and Heath mix-units (the one with no assign buttons
> over the faders). So I set up the house mix and gave the video guy
> line outs from a couple of aux sends. He was telling me he needed more
> signal so after almost maxing out the aux send levels I started
> cranking the pre-amps, still not enough, and we were starting to hear
> hiss in the video audio because the pres were so maxed out. We tried
> switching audio input level sources on the camera and finally arrived
> at a compromise we could live with.
> So what is going on here? The video guy is telling me that broadcast
> levels for inputing audio to the camera should be at +30 instead of my
> line level of +4 from the board. Any help?


That does not sound correct
get the model of the camera , do a google for the owners manual and read it
george

[Richard Crowley]

"frogfeet" wrote ...
> Hi folks, recently i did sound for a folk concert and had to provide a
> feed to the video guy. The board they provided me with was
> one of those Allen and Heath mix-units (the one with no assign buttons
> over the faders). So I set up the house mix and gave the video guy
> line outs from a couple of aux sends. He was telling me he needed more
> signal so after almost maxing out the aux send levels I started
> cranking the pre-amps, still not enough, and we were starting to hear
> hiss in the video audio because the pres were so maxed out. We tried
> switching audio input level sources on the camera and finally arrived
> at a compromise we could live with.
> So what is going on here? The video guy is telling me that broadcast
> levels for inputing audio to the camera should be at +30 instead of my
> line level of +4 from the board. Any help?

That's absurd. He must have had a 20dB pad in there somewhere
that he didn't know about. +30 would overdrive any camera input
circuit I've ever heard of.

Assuming there wasn't some kind of line-level/mic-level switch on
the A&H output?

[Mark]

On Oct 13, 4:27*pm, "Richard Crowley" > wrote:
> "frogfeet" wrote ...
>
> > Hi folks, recently i did sound for a folk concert and had to provide a
> > feed to the video guy. The board they provided me with was
> > one of those Allen and Heath mix-units (the one with no assign buttons
> > over the faders). So I set up the house mix and gave the video guy
> > line outs from a couple of aux sends. He was telling me he needed more
> > signal so after almost maxing out the aux send levels I started
> > cranking the pre-amps, still not enough, and we were starting to hear
> > hiss in the video audio because the pres were so maxed out. We tried
> > switching audio input level sources on the camera and finally arrived
> > at a compromise we could live with.
> > So what is going on here? The video guy is telling me that broadcast
> > levels for inputing audio to the camera should be at +30 instead of my
> > line level of +4 from the board. Any help?
>
> That's absurd. *He must have had a 20dB pad in there somewhere
> that he didn't know about. *+30 would overdrive any camera input
> circuit I've ever heard of.
>
> Assuming there wasn't some kind of line-level/mic-level switch on
> the A&H output?

was it one of the A&H dual mode models like the GL2200 that have a
mode switch that basically swap the functions of the AUXs and the
GROUPSs?


Mark

[frogfeet]

On Oct 13, 4:27*pm, "Richard Crowley" > wrote:
> "frogfeet" wrote ...
>
> > Hi folks, recently i did sound for a folk concert and had to provide a
> > feed to the video guy. The board they provided me with was
> > one of those Allen and Heath mix-units (the one with no assign buttons
> > over the faders). So I set up the house mix and gave the video guy
> > line outs from a couple of aux sends. He was telling me he needed more
> > signal so after almost maxing out the aux send levels I started
> > cranking the pre-amps, still not enough, and we were starting to hear
> > hiss in the video audio because the pres were so maxed out. We tried
> > switching audio input level sources on the camera and finally arrived
> > at a compromise we could live with.
> > So what is going on here? The video guy is telling me that broadcast
> > levels for inputing audio to the camera should be at +30 instead of my
> > line level of +4 from the board. Any help?
>
> That's absurd. *He must have had a 20dB pad in there somewhere
> that he didn't know about. *+30 would overdrive any camera input
> circuit I've ever heard of.
>
> Assuming there wasn't some kind of line-level/mic-level switch on
> the A&H output?

I didn't note the camera model, it appeared to be an older
professional panasonic with a Leica lens, it had XLR audio inputs.

[Richard Crowley]

"frogfeet" > wrote in message
...
On Oct 13, 4:27 pm, "Richard Crowley" > wrote:
> "frogfeet" wrote ...
>
> > Hi folks, recently i did sound for a folk concert and had to provide a
> > feed to the video guy. The board they provided me with was
> > one of those Allen and Heath mix-units (the one with no assign buttons
> > over the faders). So I set up the house mix and gave the video guy
> > line outs from a couple of aux sends. He was telling me he needed more
> > signal so after almost maxing out the aux send levels I started
> > cranking the pre-amps, still not enough, and we were starting to hear
> > hiss in the video audio because the pres were so maxed out. We tried
> > switching audio input level sources on the camera and finally arrived
> > at a compromise we could live with.
> > So what is going on here? The video guy is telling me that broadcast
> > levels for inputing audio to the camera should be at +30 instead of my
> > line level of +4 from the board. Any help?
>
> That's absurd. He must have had a 20dB pad in there somewhere
> that he didn't know about. +30 would overdrive any camera input
> circuit I've ever heard of.
>
> Assuming there wasn't some kind of line-level/mic-level switch on
> the A&H output?

I didn't note the camera model, it appeared to be an older
professional panasonic with a Leica lens, it had XLR audio inputs.

[frogfeet]

On Oct 13, 5:26*pm, frogfeet > wrote:
> On Oct 13, 4:27*pm, "Richard Crowley" > wrote:
>
>
>
>
>
> > "frogfeet" wrote ...
>
> > > Hi folks, recently i did sound for a folk concert and had to provide a
> > > feed to the video guy. The board they provided me with was
> > > one of those Allen and Heath mix-units (the one with no assign buttons
> > > over the faders). So I set up the house mix and gave the video guy
> > > line outs from a couple of aux sends. He was telling me he needed more
> > > signal so after almost maxing out the aux send levels I started
> > > cranking the pre-amps, still not enough, and we were starting to hear
> > > hiss in the video audio because the pres were so maxed out. We tried
> > > switching audio input level sources on the camera and finally arrived
> > > at a compromise we could live with.
> > > So what is going on here? The video guy is telling me that broadcast
> > > levels for inputing audio to the camera should be at +30 instead of my
> > > line level of +4 from the board. Any help?
>
> > That's absurd. *He must have had a 20dB pad in there somewhere
> > that he didn't know about. *+30 would overdrive any camera input
> > circuit I've ever heard of.
>
> > Assuming there wasn't some kind of line-level/mic-level switch on
> > the A&H output?
>
> I didn't note the camera model, it appeared to be an older
> professional panasonic with a Leica lens, it had XLR audio inputs.

The board was the A&H mix-wizard 16:2

[Richard Crowley]

"frogfeet" wrote ...
> I didn't note the camera model, it appeared to be an older
> professional panasonic with a Leica lens, it had XLR audio inputs.

Yes, and most of them have a built-in pad so they can accomodate
mic level (many with P48 phantom power) or line-level (through the
mic preamp, but with the pad knocking the signal down to mic-level).

But none of them require (or will even tollerate) +30dB. It would
take an external pad to make them THAT remarkably insensitive.

[Scott Dorsey]

In article >,
frogfeet > wrote:
>On Oct 13, 4:27=A0pm, "Richard Crowley" > wrote:
>> "frogfeet" wrote ...
>>
>> > Hi folks, recently i did sound for a folk concert and had to provide a
>> > feed to the video guy. The board they provided me with was
>> > one of those Allen and Heath mix-units (the one with no assign buttons
>> > over the faders). So I set up the house mix and gave the video guy
>> > line outs from a couple of aux sends. He was telling me he needed more
>> > signal so after almost maxing out the aux send levels I started
>> > cranking the pre-amps, still not enough, and we were starting to hear
>> > hiss in the video audio because the pres were so maxed out. We tried
>> > switching audio input level sources on the camera and finally arrived
>> > at a compromise we could live with.
>> > So what is going on here? The video guy is telling me that broadcast
>> > levels for inputing audio to the camera should be at +30 instead of my
>> > line level of +4 from the board. Any help?
>>
>> That's absurd. =A0He must have had a 20dB pad in there somewhere
>> that he didn't know about. =A0+30 would overdrive any camera input
>> circuit I've ever heard of.
>>
>> Assuming there wasn't some kind of line-level/mic-level switch on
>> the A&H output?
>
>I didn't note the camera model, it appeared to be an older
>professional panasonic with a Leica lens, it had XLR audio inputs.

There are some Panasonics which have line level inputs on phono jacks and
XLR mike inputs. If you were feeding the mike input and the switch was
set to line, the level might be pretty low but there might be enough leakage
to hear a little bit with the gain cranked way up.

Video people should never be allowed to touch anything to do with sound.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Richard Crowley]

"Scott Dorsey" wrote ...
> There are some Panasonics which have line level inputs on phono jacks and
> XLR mike inputs. If you were feeding the mike input and the switch was
> set to line, the level might be pretty low but there might be enough
> leakage
> to hear a little bit with the gain cranked way up.

That should be good for at least 40dB of "padding". :-)

> Video people should never be allowed to touch anything to do with sound.

I had 15+ years doing sound before ever touching video, so I
still consider myself an audio person who also does video. :-)
I only got into video because the audio was so bad, I thought
I could try to bring the quality up a bit.

[Mike Rivers]

frogfeet wrote:
> Hi folks, recently i did sound for a folk concert and had to provide a
> feed to the video guy. The board they provided me with was
> one of those Allen and Heath mix-units (the one with no assign buttons
> over the faders). So I set up the house mix and gave the video guy
> line outs from a couple of aux sends.

That's the way I'd do it. So far so good. That way you have independent
control over the level that the camera is getting.

> He was telling me he needed more
> signal so after almost maxing out the aux send levels I started
> cranking the pre-amps, still not enough

Obviously something was wrong with the way the gozoutas were
getting to the gozintas. It could be a miswired cable, a level setting
on either the console or the camera, or, as Scott suggests, a half brain
dead cameraman. At this point, and probably forever, we have
insufficient information to make a good guess.

Were you going from 1/4" output jacks on the mixer to XLRs on the
camera? That's a mistake waiting to happen because they could be
wired wrong for the particular setup. There are several possibilities.

> So what is going on here? The video guy is telling me that broadcast
> levels for inputing audio to the camera should be at +30 instead of my
> line level of +4 from the board. Any help?

He clearly is off the mark here, at least in his understanding of
levels. +4 dBu
nominal output should be capable of giving you peaks of +22 to +26 dBu. The
"+30" he told you was probably maximum input level before clipping, which
is pretty hot. I suspect miswiring or misadjustment.

But for future reference, when you have a problem like this, you apply a
little
brute force, but you don't keep forcing it. When it should work right
and it
doesn't, you need to find out why it doesn't. Don't leave home without a
pocket full of XLR-1/4" adapters and pin 2x3 changers.

[frogfeet]

On Oct 13, 8:09*pm, Mike Rivers > wrote:
> frogfeet wrote:
> > Hi folks, recently i did sound for a folk concert and had to provide a
> > feed to the video guy. The board they provided me with was
> > one of those Allen and Heath mix-units (the one with no assign buttons
> > over the faders). So I set up the house mix and gave the video guy
> > line outs from a couple of aux sends.
>
> That's the way I'd do it. So far so good. That way you have independent
> control over the level that the camera is getting.
>
> *> He was telling me he needed more
>
> > signal so after almost maxing out the aux send levels I started
> > cranking the pre-amps, still not enough
>
> Obviously something was wrong with the way the gozoutas were
> getting to the gozintas. It could be a miswired cable, a level setting
> on either the console or the camera, or, as Scott suggests, a half brain
> dead cameraman. At this point, and probably forever, we have
> insufficient information to make a good guess.
>
> Were you going from 1/4" output jacks on the mixer to XLRs on the
> camera? That's a mistake waiting to happen because they could be
> wired wrong for the particular setup. There are several possibilities.
>
> > So what is going on here? The video guy is telling me that broadcast
> > levels for inputing audio to the camera should be at +30 instead of my
> > line level of +4 from the board. Any help?
>
> He clearly is off the mark here, at least in his understanding of
> levels. +4 dBu
> nominal output should be capable of giving you peaks of +22 to +26 dBu. The
> "+30" he told you was probably maximum input level before clipping, which
> is pretty hot. I suspect miswiring or misadjustment.
>
> But for future reference, when you have a problem like this, you apply a
> little
> brute force, but you don't keep forcing it. When it should work right
> and it
> doesn't, you need to find out why it doesn't. Don't leave home without a
> pocket full of XLR-1/4" adapters and pin 2x3 changers.

Thanks Mike, very clear answer. I did use high quality XLR-1/4''
adaptors and also tried changing cables so I'm guessing it was the
video guy's fault.