Audio Bitrate?

[JermBos]

Just wondering what you people set your audio bitrate to. DVD2SVCD is defaulted to 128k, I usually set mine to 160k but I was wondering how much of a difference it makes. I know it makes a difference on music MP3's. Also, does making a higher audio bitrate take up more space on the CD?

[markrb]

Depends on what it is, if it will make a difference in video bitrate for a specified amount of cd's.

If it will fit no problem or heavily audio such as music based always 224.
If I can increase the video bitrate and it's not heavily music then 192.
I never use lower.

Mark

[Matthew]

More audio = less for video, but personally I think it's better to sacrifice a little video bitrate for the sake of 224 audio (just to be safe).

[Kedirekin]

Conventional wisdom is mp2 isn't at good at low bitrates as mp3. Kind-of obvious when you think about it - otherwise they wouldn't have needed to develop mp3.

128 kbps mp2 definately won't be 'near-CD quality', but is probably adequate if the original sound-track isn't that good, or if your hearing isn't that good. :)

If you care at all about the sound, I'd go with at least 192 kbps. Personally I use 224; I don't think you'll notice the loss of 96 kbps in the video bitrate, especially since the 96 comes from the average bitrate (I believe max bitrate on the bitrate tab is set to 2498 by default, right?, which I believe is the correct max for 224 audio).

[markrb]

Kedirekin just to confuse things a little more. I have a full 7 speaker plus sub Atlantic Technology setup and I did a blind listening test between 224 and 192 using the opening scene of Legally Blonde as the subject.
I had four people in the room other then myself. Nobody could tell the difference. Since that time I feel very comfortable using 192 for audio for all but the most heavily music based videos.
If there will be no difference in the video rate I do up it to 224, but if it drops my video rate then 192 seems more then fine.
Another reason is my DVD player can play 2600 kbit video perfect. So personally I will drop the audio a bit to increase the video. Even at 192 I have to uncheck the Adjust audio bitrate box on the bitrate tab.

Mark

[mrbass]

I do same as markb 192 every DVD except 224 for music/concert DVDs. Biggest improvement in audio is when that Azid had the auto-detect gain feature added a few months back. That was a boon to quality sound.

[Kedirekin]

I hear where you're coming from (no pun intended). I probably couldn't tell 192 from 224 either (my hearing isn't that good).

On the other hand, I can't tell the difference between video with max bitrate of 2498 versus max of 2530 either. So unless it is really challenging footage (like anime), I usually go with 2498 + 224.

So it's 6 of one, ½ dozen of another.

Bottom line, everyone needs to decide for themselves.

[JermBos]

alright thanks, but what video bitrate do I change, the max bitrate or the max avg. bitrate? if I want to make it 2498, I think its set right now to 2250 and 2130, won't this cause 3 or more CD's?

[markrb]

That is the bigger issue. How many cd's do you want the final result to be. In my case I don't want to drop the video any lower then I have to. I often end up re-encoding a video becuase I have an extra 100 or 200mb to play with or have a final image of 10-20mb. In the first case I raise all the bitrates a bit and in the second case I lower the video bitrate a bit if the audio was at 192 or just lower the audio to 192 if it was at 224 to have it loose that last image.
The new default values have been lowered for more compatability, but since I never had any issues I just manually set them to what I want. For my setup (my player can play above spec) I set the MAX to 2600, the Max AVG to 2450 and the Min to 1300. Of course the average adjusts automatically based on the video length, number of cd's and size of the cd's. This is where playing with the audio bitrate, number of cd's and even removing the last chapter if it's just credits comes into play.
I am a serious tweaker on most things. I want every last bit I can even if it doesn't make a bit of difference in the end product.
If you know what your DVD player can play as far as bitrate you can work from there. Play with the bitrates, you always have the default button to return. SVCD spec calls for 2500 video bitrate max. You will likely make a few coasters when playing, but if you use a CDRW when doing you testing you can just erase it. I spent 3 weeks just making test disks to find out what the max my DVD player would take without problems was. Just understand that when you go beyond the standard values it's all up to you. You will have to figure problems out for yourself.

Mark