Audio problem with downconvert on HDSDI at DVinfo.net

John Mitchell · February 4th, 2010, 09:55 PM

Hi - I have no problem with the HD-SDI embedded audio when recording hi-def on the HM700 via HD-SDI but real issues with the downconvert to SD.

On Avid via my NitrisDX box the audio is distorted and on the Convergent Design Nanoflash it is unusable (sounds like a sample rate problem) and won't import into Avid at all (sample rate error). The audio recorded in camera is fine.

Can anyone else confirm this issue on their cam?

Peter Erfurt · February 5th, 2010, 01:21 PM

I have a problem with 1 of several computers, where it makes a hissing sound on and off, rendering the sound unusable.

This only happens on one of the computers with Premiere Pro - if I use for example Edius, there's no problem. And if I use another computer with Premiere Pro - then there is no problem either.

The computer in question runs 64-bit Windows 7, so that may have something to do with the problem, but untill now I have failed to clearly locate the problem. I even shifted the soundcard on this computer - but problem still exists. So I'm leaning against a OS problem of some sort.

/peter

John Mitchell · February 5th, 2010, 06:58 PM

Sorry Peter - I think I missed the connection there? Are we talking about the same thing - downconverted Standard definition material from the SDI port of the JVC GY-HM700?

Peter Erfurt · February 5th, 2010, 07:39 PM

Sorry, NO - but then again in a sense yes = sound problems with the output from 700 (!)

But I agree - your problem is not at all the same as mine, but what I'm saying is, that there COULD be issues with the way the 700 presents sound to a computer, hence we have different problems in the NLE systems ??

/peter

John Mitchell · February 7th, 2010, 10:33 PM

Peter I'd say our problems are not at all related. I have had no issue with the sound of the SD cards that record in camera. My problem is entirely related to the HD-SDI port and ONLY on downconvert.

Your problem sounds like a Premiere Pro compatibility issue with the soundcard in that particular machie. It may not be hardware related but could be a software issue such as direct x - keep in mind different software applications call up different decoders to deal with audio and video.

HTH

John

February 4th, 2010, 09:55 PM	#1
John Mitchell Contributor Join Date: Jul 2005 Location: Sydney Australia Posts: 873	Audio problem with downconvert on HDSDI Hi - I have no problem with the HD-SDI embedded audio when recording hi-def on the HM700 via HD-SDI but real issues with the downconvert to SD. On Avid via my NitrisDX box the audio is distorted and on the Convergent Design Nanoflash it is unusable (sounds like a sample rate problem) and won't import into Avid at all (sample rate error). The audio recorded in camera is fine. Can anyone else confirm this issue on their cam?

February 5th, 2010, 01:21 PM	#2
Peter Erfurt Regular Crew Join Date: Oct 2006 Location: Silkeborg Denmark Posts: 93	I have a problem with 1 of several computers, where it makes a hissing sound on and off, rendering the sound unusable. This only happens on one of the computers with Premiere Pro - if I use for example Edius, there's no problem. And if I use another computer with Premiere Pro - then there is no problem either. The computer in question runs 64-bit Windows 7, so that may have something to do with the problem, but untill now I have failed to clearly locate the problem. I even shifted the soundcard on this computer - but problem still exists. So I'm leaning against a OS problem of some sort. /peter

February 5th, 2010, 06:58 PM	#3
John Mitchell Contributor Join Date: Jul 2005 Location: Sydney Australia Posts: 873	Sorry Peter - I think I missed the connection there? Are we talking about the same thing - downconverted Standard definition material from the SDI port of the JVC GY-HM700?

February 5th, 2010, 07:39 PM	#4
Peter Erfurt Regular Crew Join Date: Oct 2006 Location: Silkeborg Denmark Posts: 93	Sorry, NO - but then again in a sense yes = sound problems with the output from 700 (!) But I agree - your problem is not at all the same as mine, but what I'm saying is, that there COULD be issues with the way the 700 presents sound to a computer, hence we have different problems in the NLE systems ?? /peter

February 7th, 2010, 10:33 PM	#5
John Mitchell Contributor Join Date: Jul 2005 Location: Sydney Australia Posts: 873	Peter I'd say our problems are not at all related. I have had no issue with the sound of the SD cards that record in camera. My problem is entirely related to the HD-SDI port and ONLY on downconvert. Your problem sounds like a Premiere Pro compatibility issue with the soundcard in that particular machie. It may not be hardware related but could be a software issue such as direct x - keep in mind different software applications call up different decoders to deal with audio and video. HTH John