Mac Pro adds Audio Crackle to DVCPro HD via Firewire
by walter biscardi
on
Mar 21, 2007 at 2:32:24 pm
Hi folks,
We've been chasing down an audio issue with Panasonic for the past three weeks and we have finally determined it is the Mac Pro Quad 3.0 that is causing the issue.
What happens is a high end audio crackle, like sizzling bacon or crinkling cellophane, is added to the audio when mastering out to the Panasonic 1400 deck via Firewire. Via HD-SDI through the Kona 3 everything is fine.
We finally moved the project and the deck to our Power PC Quad G5 and the issue went away. Went back to the Mac Pro and the issue reappears.
Our audio engineer feels it is a word clock issue with the Mac Pro and we're going to see if we can fix this on our end. I'll update you if we get a fix.
Walter Biscardi, Jr.
http://www.biscardicreative.com
HD Editorial & Animation for Food Network's "Good Eats"
HD Editorial for "Assignment Earth"
"I reject your reality and substitute my own!" - Adam Savage, Mythbusters
Re: Mac Pro adds Audio Crackle to DVCPro HD via Firewire by walter biscardi on Mar 21, 2007 at 9:28:19 pm
[JeremyG]"FWIW, I lay off to DVCPRO HD via HD-SDI all the time and never get any complaints."
I can honestly say I can see a difference between the Firewire output and the SDI output. When laying off via Firewire there's zero compression added by the deck. When laying off via HD-SDI, there is another layer of "light compression" (Panasonic's words) added by the deck.
When I compare the two back to back I can see subtle differences in the dark areas of the screen especially. Nothing the home viewer will notice and nothing the network would kick back, but it's there.
Ingesting, there's zero difference between FW and SDI, but for mastering, it is there, especially on a large plasma HD screen.
Walter Biscardi, Jr.
http://www.biscardicreative.com
HD Editorial & Animation for Food Network's "Good Eats"
HD Editorial for "Assignment Earth"
"I reject your reality and substitute my own!" - Adam Savage, Mythbusters
Re: Mac Pro adds Audio Crackle to DVCPro HD via Firewire by Wayne Carey on Mar 21, 2007 at 3:42:37 pm
[walter biscardi]"What happens is a high end audio crackle, like sizzling bacon or crinkling cellophane, is added to the audio when mastering out to the Panasonic 1400 deck via Firewire. Via HD-SDI through the Kona 3 everything is fine."
Don't mean to throw you a curve ball...
But I recently had a program that the audio levels were recorded low and I used the rule of twos to bring it backup thru the Audio Compressor/Limiter filter. This audio was recorded outside in the cold so the camera guy stuck the lavs down inside of their clothing a little too far. I had to give it some serious high end EQ to get decent audio. As soon as I did this... I heard the high end crackle that you speak of, too.
We are using the Kona 3 to output HD-SDI to our PDW-70 deck and the programs are edited DVCProHD 1080i29.97. I have noticed this crackle for a little while but it has not been real annoying until this program.
Now, there's always been an issue of the pops and crackles with the Kona 3. Of which, is getting really really annoying to me. I have this to happen at least 2 out of 5 times that I play the timeline and almost does this on output until I stop it and restart Print to Video. Maybe these issues are related.
Has anyone else seen these issues?
_______________________________
Wayne Carey
Schazam Productions
www.schazamproductions.com
Re: Mac Pro adds Audio Crackle to DVCPro HD via Firewire by walter biscardi on Mar 21, 2007 at 5:02:22 pm
[Wayne Carey]"Now, there's always been an issue of the pops and crackles with the Kona 3. Of which, is getting really really annoying to me. I have this to happen at least 2 out of 5 times that I play the timeline and almost does this on output until I stop it and restart Print to Video. Maybe these issues are related."
That issue has never happened here during Edit to Tape, only during playback. Yep, it's an annoying issue and I know that AJA has been working to address it.
Walter Biscardi, Jr.
http://www.biscardicreative.com
HD Editorial & Animation for Food Network's "Good Eats"
HD Editorial for "Assignment Earth"
"I reject your reality and substitute my own!" - Adam Savage, Mythbusters
Re: Mac Pro adds Audio Crackle to DVCPro HD via Firewire by walter biscardi on Sep 24, 2009 at 12:39:28 am
[Matt Callac]"Walter, Did you guys ever find a fix for this problem? We're wanting to layoff via firewire and we're having the crackling porblem. thanks "
Nope, we switched to HD-SDI throughput back then and haven't ever had a need for firewire again.
Walter Biscardi, Jr.
Editor, Colorist, Director, Writer, Consultant, Author.
Credits include multiple Emmy, Telly, Aurora and Peabody Awards.
Owner, Biscardi Creative Media featuring HD Post Biscardi Creative Media
Creative Cow Forum Host:
Apple Final Cut Pro, Apple Motion, Apple Color, AJA Kona, Business & Marketing, Maxx Digital.
