Standard def audio sample rate issue at DVinfo.net

John Mitchell · February 4th, 2010, 06:59 AM

I'm having an issue with recording standard def from the HD-SDI port of the JVC GY-HM700.
The audio appears corrupted in the Sony clip viewer and when I try to import the clips into Avid I get a sample rate error. I'm using MXF format, 50Mbs standard def on the Nano.

The audio corruption certainly sounds like an "unlocked" sample rate issue.

I'm trying to think how else I can test the camera to rule it out - I'll try to record live to my Avid I guess, setting the Avid to internal sync lock as the JVC has no sync input.

John Mitchell · February 4th, 2010, 07:47 PM

OK - I can rule out he JVC for the audio late thing as well as the phasing issue. I checked on Avid and the audio straight out of the HD-SDI port compared to the recorded material on the camera is pretty close to identical in timing.

However the audio embedded in the HD-SDI during a standard def downconvert appears to be a JVC issue. When I tried to record this audio directly to Avid it was quite distorted. I think it is over to JVC on that one - Iguess I can go analogue out of the camera straight into the Nano as a workaround.

February 4th, 2010, 06:59 AM	#1
John Mitchell Contributor Join Date: Jul 2005 Location: Sydney Australia Posts: 873	Standard def audio sample rate issue I'm having an issue with recording standard def from the HD-SDI port of the JVC GY-HM700. The audio appears corrupted in the Sony clip viewer and when I try to import the clips into Avid I get a sample rate error. I'm using MXF format, 50Mbs standard def on the Nano. The audio corruption certainly sounds like an "unlocked" sample rate issue. I'm trying to think how else I can test the camera to rule it out - I'll try to record live to my Avid I guess, setting the Avid to internal sync lock as the JVC has no sync input.

February 4th, 2010, 07:47 PM	#2
John Mitchell Contributor Join Date: Jul 2005 Location: Sydney Australia Posts: 873	Further info and tests OK - I can rule out he JVC for the audio late thing as well as the phasing issue. I checked on Avid and the audio straight out of the HD-SDI port compared to the recorded material on the camera is pretty close to identical in timing. However the audio embedded in the HD-SDI during a standard def downconvert appears to be a JVC issue. When I tried to record this audio directly to Avid it was quite distorted. I think it is over to JVC on that one - Iguess I can go analogue out of the camera straight into the Nano as a workaround.