DVX-100b Creeping Sound Levels? at DVinfo.net

Jeffery Magat · September 4th, 2009, 07:13 AM

I haven't used the Panasonic DVX-100b cameras in a while, but recently I've had an onslaught of jobs with this camera. What I'm finding extremely problematic is the fact that when I send tone to the camera, it'll slowly creep up 8 dBu over a 1-2 minute period. Oh yeah, and AGC is off. This has happened on two cameras already.. I end up having to calibrate the levels inaccurately and trying to make sure I'm not clipping to the camera.

What's the deal? I'm pretty sure this wasn't occurring when I've used this a while back.

Rick Reineke · September 4th, 2009, 10:43 AM

This is a known issue with DVX series, The camera needs to 'warm up' some to stabilize.

Jeffery Magat · September 4th, 2009, 11:36 AM

Doesn't quite make sense to me. What I did was send out full scale tone from my 302, and let it 'warm up' and set my levels. Comparing my meters to the cams meters of just talking into my mic wasn't quite lining up. I guess I'll have to go on cheating my levels.

Rick Reineke · September 4th, 2009, 05:17 PM

I assumed you meant the levels were eratic.
I had the same issue with two JVC HD-GY250s. The camera levels just did not coincide with full-scale tone. After setting full-scale tone on the camera, then rechecking normal OdB tone showed -28dB on the camera, a discrepancy of 8dB! My work-around, I backed off the tone to -7dB on the 302 and set the camera to -20dB and everything lines up normal. BIZARRE! PB sounded fine and no complaints from post.
I asked a JVC US rep... they he didn't know.
I just have to remember to set the tone back to 0dB on my 302.
That said, I've never had that issue with HVX cameras or any other for that matter.

Marco Leavitt · September 9th, 2009, 09:23 AM

Panasonic in general is just terrible for this. There are some DVXs, no matter how long they warm up, that won't hold stable levels. The problem can be minor or catastrophic. I was on a shoot a couple of weeks ago in which they had a brand new DVX100b, and it would fluctuate 8dB or more, just as you say. The HVX200 is similarly plagued. Pity, as both these cameras have better than average sound.

Tom Hardwick · September 9th, 2009, 09:34 AM

Quote:

Originally Posted by Marco Leavitt

it would fluctuate 8dB or more. Pity, as both these cameras have better than average sound.

Er - a fluctuation of 8dB is huge. I wonder what an 'average' camera fluctuates by for the Panasonic to have better sound.

Marco Leavitt · September 9th, 2009, 10:26 AM

By that I mean the quality of the preamps. Not all DVXs are that bad, but I've run into a few.

September 4th, 2009, 07:13 AM	#1
Jeffery Magat Regular Crew Join Date: Feb 2007 Location: Toronto, ON Posts: 186	DVX-100b Creeping Sound Levels? I haven't used the Panasonic DVX-100b cameras in a while, but recently I've had an onslaught of jobs with this camera. What I'm finding extremely problematic is the fact that when I send tone to the camera, it'll slowly creep up 8 dBu over a 1-2 minute period. Oh yeah, and AGC is off. This has happened on two cameras already.. I end up having to calibrate the levels inaccurately and trying to make sure I'm not clipping to the camera. What's the deal? I'm pretty sure this wasn't occurring when I've used this a while back.

September 4th, 2009, 10:43 AM	#2
Rick Reineke Inner Circle Join Date: Aug 2008 Location: New York Posts: 2,039	This is a known issue with DVX series, The camera needs to 'warm up' some to stabilize.

September 4th, 2009, 11:36 AM	#3
Jeffery Magat Regular Crew Join Date: Feb 2007 Location: Toronto, ON Posts: 186	Doesn't quite make sense to me. What I did was send out full scale tone from my 302, and let it 'warm up' and set my levels. Comparing my meters to the cams meters of just talking into my mic wasn't quite lining up. I guess I'll have to go on cheating my levels.

September 4th, 2009, 05:17 PM	#4
Rick Reineke Inner Circle Join Date: Aug 2008 Location: New York Posts: 2,039	I assumed you meant the levels were eratic. I had the same issue with two JVC HD-GY250s. The camera levels just did not coincide with full-scale tone. After setting full-scale tone on the camera, then rechecking normal OdB tone showed -28dB on the camera, a discrepancy of 8dB! My work-around, I backed off the tone to -7dB on the 302 and set the camera to -20dB and everything lines up normal. BIZARRE! PB sounded fine and no complaints from post. I asked a JVC US rep... they he didn't know. I just have to remember to set the tone back to 0dB on my 302. That said, I've never had that issue with HVX cameras or any other for that matter.

September 9th, 2009, 09:23 AM	#5
Marco Leavitt Inner Circle Join Date: Jul 2002 Location: Albany, NY 12210 Posts: 2,652	Panasonic in general is just terrible for this. There are some DVXs, no matter how long they warm up, that won't hold stable levels. The problem can be minor or catastrophic. I was on a shoot a couple of weeks ago in which they had a brand new DVX100b, and it would fluctuate 8dB or more, just as you say. The HVX200 is similarly plagued. Pity, as both these cameras have better than average sound.

September 9th, 2009, 10:26 AM	#7
Marco Leavitt Inner Circle Join Date: Jul 2002 Location: Albany, NY 12210 Posts: 2,652	By that I mean the quality of the preamps. Not all DVXs are that bad, but I've run into a few.