HD200 Audio at DVinfo.net

Go Back   DV Info Net > JVC ProHD & MPEG2 Camera Systems > JVC GY-HD Series Camera Systems

JVC GY-HD Series Camera Systems
GY-HD 100 & 200 series ProHD HDV camcorders & decks.


Reply
 
Thread Tools Search this Thread
Old August 16th, 2007, 09:12 PM   #1
New Boot
 
Join Date: Jan 2007
Location: Miami, FL
Posts: 12
HD200 Audio

Hello everyone,

I'm a little baffled with the audio settings in my camera. I think there may be something wrong or if there isn't, can someone please explain it to me. First of all, switching the audio reference from -20dB to -12dB does what it should. The reference dot in the bar scale moves and the graph is "rescaled" with whatever dB is set where the dot is the peak. Switching between -12 and -20 will automatically increase/decrease level and keep the audio peaked at the reference dot (without me manually adjusting the wheel). The output level will be at -12dB or -20dB in an NLE as it should.

However..I think there is a problem with the input mic reference. When I switch from -50 to -60...the audio levels go up. Shouldn't it be the opposite? The audio is boosted the same way as it would go from -20 to -12. The audio is set to manual, btw. If anyone can explain why it does that, I would appreciate it.

-alan
Alan Hanna is offline   Reply With Quote
Old August 16th, 2007, 09:19 PM   #2
Major Player
 
Join Date: Mar 2005
Posts: 423
Quote:
Originally Posted by Alan Hanna View Post
Hello everyone,
...
However..I think there is a problem with the input mic reference. When I switch from -50 to -60...the audio levels go up. Shouldn't it be the opposite? The audio is boosted the same way as it would go from -20 to -12. The audio is set to manual, btw. If anyone can explain why it does that, I would appreciate it.
-alan
This is the way I guess it works:

Assuming the same audio source, the pysical input level is remaining contant. Therefore, if you change the input mic reference level from -50 to -60 you are telling the camera the level of the reference input level from the mic is lower than before (was -50, now -60) therefore the camera will compensate by increaseing the levels (as you say they go up). To me it sounds like it is doing what it should be doing.
Guy Barwood is offline   Reply With Quote
Old August 16th, 2007, 09:52 PM   #3
New Boot
 
Join Date: Jan 2007
Location: Miami, FL
Posts: 12
Thanks, Guy.

That makes sense. I was thinking of it in the same terms as the audio reference level. I knew that there had to be a reason for it...I just wasnt sure what it was.

-alan
Alan Hanna is offline   Reply With Quote
Old August 17th, 2007, 12:04 AM   #4
Trustee
 
Join Date: Apr 2006
Location: United States
Posts: 1,158
the change is as expected. the difference is you are adding a -10db pad in using the -50 setting, so when you change to -60, the level goes up. this setting changes the actual input level, while the other one simple moves the ref point in the display.

personally I find that using -20 is wasting a lot of audio space if you are working with a external mixer. I usually run tone thru and turn on 2 more segments which should be about -14. even with that level, the mixer will clip before the camera will hit 0 and clip. if you are tighter with the levels, I'm sure you could run -12, but that takes more care.
Steve Oakley is offline   Reply With Quote
Old August 18th, 2007, 06:24 PM   #5
New Boot
 
Join Date: Jan 2007
Location: Miami, FL
Posts: 12
Quote:
Originally Posted by Steve Oakley View Post
the change is as expected. the difference is you are adding a -10db pad in using the -50 setting, so when you change to -60, the level goes up. this setting changes the actual input level, while the other one simple moves the ref point in the display.

personally I find that using -20 is wasting a lot of audio space if you are working with a external mixer. I usually run tone thru and turn on 2 more segments which should be about -14. even with that level, the mixer will clip before the camera will hit 0 and clip. if you are tighter with the levels, I'm sure you could run -12, but that takes more care.
switching between -12 and -20 also changes the input level...not just the reference point. The display will rescale the meter and increase (or decrease) the level so it peaks at the ref point.

I have also noticed that switching from -50 to -60 blocks out a lot of outside noise and hissing much better than using -50...but the input volume wheel is usually set between 1-3...instead of 5-7 when using -50 during interviews. So if the interviewee talks a little bit louder or suddenly yells than he/she should it looks like it can cause trouble. I've always kept it at -50. But in a controlled environment...it isnt really a big issue since the volume frmo the speaker will probably remain at a constant level anyway.

-alan
Alan Hanna is offline   Reply With Quote
Old August 18th, 2007, 08:44 PM   #6
Major Player
 
Join Date: Mar 2003
Location: Fremantle, Western Australia
Posts: 253
Another possibility is to set channel 1 to -60 and put the pad on channel 2 as your safety channel just in case channel 1 clips (use the setting on the camera to set input 1 to both channels).

I too use an external preamp/mixer whenever possible. Going line level in to the camera will definitely give a much better sound than using the onboard preamps.

Rob
Robert Castiglione is offline   Reply With Quote
Old August 19th, 2007, 11:54 AM   #7
New Boot
 
Join Date: Jan 2007
Location: Miami, FL
Posts: 12
Quote:
Originally Posted by Robert Castiglione View Post
Another possibility is to set channel 1 to -60 and put the pad on channel 2 as your safety channel just in case channel 1 clips (use the setting on the camera to set input 1 to both channels).

I too use an external preamp/mixer whenever possible. Going line level in to the camera will definitely give a much better sound than using the onboard preamps.

Rob
Robert,

That is a good idea. I'll start doing that. I've never been an audio guru...lol. Just shooting and doing audio whenever I had to do interviews. Most of the time I shoot video for b-roll purposes with just NAT sound. But the most annoying of all is taking a Beta SP tape with proper audio levels to an SX deck for playback. That is pretty much an audio nightmare...lol. Especially if you edit on SP and take it to SX for playback...audio levels just overmodulate going from the analog to digital.

thanks
-alan
Alan Hanna is offline   Reply With Quote
Old August 19th, 2007, 06:59 PM   #8
Major Player
 
Join Date: Mar 2003
Location: Fremantle, Western Australia
Posts: 253
Thanks Alan. Obviously, dont forget when using the two channels in this way to adjust the volume for each volume accordingly. And of course there is the switch on the camera for monitoring each channel separately.

I have to confess to loving the audio side of things. I just think it is possible to get it right without necessarily having a separate audio guy if that is not in the budget.

Rob
Robert Castiglione is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > JVC ProHD & MPEG2 Camera Systems > JVC GY-HD Series Camera Systems

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 05:39 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network