Audio Capture - 32 Khz vs 48 Khz

[badgerboy]

Sort of a newbie question. When I capture, using any of several capture utilities, the resulting AVIs always have 32 Khz audio. (I capture via firewaire to AVI format). I know that the DVD standard requires 48 Khz, and assume that when I encode for DVD whatever app I use takes care of that translation. But why do all my captures come in at 32 Khz? Is that what my DV camcorder outputs (Sony DCR-TRV740 NTSC)? I can't find anything in the camcorder documentation or settings about the audio bitrate, and can't find any way to modify it in the capture apps (Scenealyzer, Pinnacle S8, EditStudio). Should I be worried about the 32 Khz captures, or just assume that when I edit and encode for DVD it will be taken care of? Thanks for any advice! (I have read all the guides, articles and back posts in the audio section, but cannot find anything on this)

[Cornucopia]

Are you also running your DV camera in LP mode?
AFAIK, that would be the ONLY reason for using 32k (or 4 ch. audio--but there is no such thing as a 4ch capable consumer cam). Unfortunately, some cam makers have it set for 32k by default!!!
Get out your cam manual or go to the cam user bboards and find the menu where you can change the audio samplerate setting. If you don't use the LP speed setting, then change the samplerate to 48k and leave it there. For good! 32k is noticeably less quality than either 44.1 or 48k options.

This should now be reflected in your capture settings. If not, go to their bboards and find out how (or read the manual--it should be there) to change the cap preferences.

Yes, your apps are probably re-encoding (you would have known if they weren't--you'd have a non-compliant and unplayable DVD), but there's no need for you to waste extra time and energy (and quality) every encode, just to get back to where you should have been to begin with. And my guess is they aren't optimized for this type of job and are therefore slower and of lesser quality than those apps that specialize in SRC.

HTH,
Scott

[energy80s]

Always record DV video with 48k sound. The 32k option is only if you want to audio dub the soundtrack on the original tape at a later date. It doesn't matter whether you are recording in SP or LP the 48k option is available for both.

[racer-x]

Just to simplify:

Camcorder Audio set @ 12 bits = 32 khz

Camcorder Audio set @ 16 bits = 48 khz


Always set your Camcorder Audio to 16 bit mode.

[badgerboy]

Racer-x: Thank you! That is the only setting that my camera allows me to modify. But I'm still a little confused - the manual says that 12-bit gives me "two stereo sounds," while 16-bit gives me "one stereo sound." Beyond that the manual and the camcorder menu are silent as to audio options. I cannot locate any other audio option on this camcorder that is user-modifiable! These manual instructions are a little hard to interpret; what in the world is "one" stereo sound?

[racer-x]

They refere 12 bit as 2 stereos because it is 4 chanel. They refere 16 bit as one stereo because it is 2 chanel.

The bottum line is 16 bit is better quality. If you have the camcorder set @ 12 bit, you'll have to upsample to get 48 khz. You don't need the 4 channel if you edit your video, because you can import any audio you want into your video editor.

Hope that helps.