- Audio dropout problem
- Posted by Richard Nottage on October 18th, 2003
Ok. Got a weird one here.
I have a first generation D8 (Sony trv310) camera. I've had this for
3-4 years and never have experienced this problem before.
When doing a firewire capture I get a dropout of the audio. The
waveform shows complete silence (0dbfs) for the duration (~ 1/10th of
a second) of the dropout. Video is fine, no dropped frames at all.
If I monitor the analog outputs (headphone) at the camera I hear the
audio without any dropout so the audio is there. I've tested by
capturing to two different systems using two different firewire cables
and capturing with three different capture programs on each system.
All resulted in audio dropout at the same point.
Anyone got any ideas as to what could be happening?
Gentlemen, Eat my shorts ($1 to Bart)
- Posted by Sanman on October 18th, 2003
"Richard Nottage" <nospam@forme.com> wrote in message
news:g292pv0ubmnrp785b0rlsod0e5q7upvgf6@4ax.com...
I'm guessing that there may be some sort of drop out on the tape and the
camera has some sort of error correction that allows you to still hear the
audio, but when the corrupt signal gets converted to DV format before
leaving the camera, that weak part can't be properly encoded, so some audio
frames are lost. I have the same problem at times, and I just use the audio
editing capabilities of my editor (Vegas) and repair the dropout by sticking
in some audio from another part of the track.
Sanman
- Posted by Gary Eickmeier on October 19th, 2003
Richard Nottage wrote:
I am having similar dropouts near the beginning and end of my tapes with
my Sony VX2000. I will investigate cleaning my heads first. Have you
ever cleaned your heads?
Gary Eickmeier
- Posted by Richard Nottage on October 20th, 2003
On Sun, 19 Oct 2003 02:58:50 GMT, Gary Eickmeier
<geickmei@tampabay.rr.com> wrote:
No I have not. I'm picking up a cleaner tape tomorrow just to give it
a try. I don't hold much stock in it solving this problem but it's
time anyway.
Are you able to hear the audio when monitoring camera playback with
headphones?
Gentlemen, Eat my shorts ($1 to Bart)
- Posted by Gary Eickmeier on October 20th, 2003
Richard Nottage wrote:
I'll check that when I get time - but I don't see why you would be able
to get good monitor sound and not in the captured footage - it all comes
from the video heads, right? I got good video when I had the audio
dropouts, but that's all I remember.
Gary Eickmeier
- Posted by Richard Nottage on October 20th, 2003
On Sat, 18 Oct 2003 15:24:07 -0400, "Sanman" <me@you.com> wrote:
The analog to digital conversion happens prior to the information
being stored on the tape. What is recorded to the tape is DV encoded
digital information. I would think any error correction would be
applied to the digital information prior to it being converted back to
analog for playback and if this is the case then I would think the
digital info traveling down the firewire would carry the error
correction also.
I could be completely wrong. After all, I have no idea why I have this
problem. :-)
I did a analog capture of the missing audio. Had to do a little
filtering to get everything to match up but it came out ok. I hope I
can solve this problem as I have several tapes of DV content being
stored on 8mm tapes.
- Posted by Richard Nottage on October 20th, 2003
On Mon, 20 Oct 2003 03:15:45 GMT, Gary Eickmeier
<geickmei@tampabay.rr.com> wrote:
I agree. The analog audio is great., No hint of any kind of error
correction or problems at all. I'm stumped.
I'll let you know if cleaning the heads did anything.
Thanks for trying to help out.
- Posted by Sanman on October 20th, 2003
I need to correct my post. I missread and thought you said "Hi8", not D8.
My last message doean't apply to D8. I have the same problem from time to
time and I notice that it seems to happen on tapes that are older or have
been used more than a few times. Sometimes the audio dropout is coupled
with a slight video glitch, but not usually. It is annoying. I too have a
D8. Do you use Hi8 tape or just regular 8mm?
Sanman
- Posted by Richard Nottage on October 20th, 2003
On Sun, 19 Oct 2003 23:46:37 -0400, "Sanman" <me@you.com> wrote:
I've always used regular 8mm tapes. Never experienced any of the nasty
things everyone was saying would happen if you use regular 8mm tapes
with the then 'Brand New D8' camera's. Ironically, I once bought a 3
pack of 8mm tapes which came with a free Hi8 tape. Guess which tape
this content is on??? :-)
Thanks for helping. I appreciate any attempt.
