15 Replies Latest reply on Feb 16, 2009 1:24 AM by Dag Norum

    Audio clips disappear when burning DVD. 48kHz 16 bit PCM

    (Johnie) Level 1
      Audio disappears when burning DVD. I hear the audio played back in the timeline but when I play the DVD the audio is not there.
      Odd things to ponder:
      1. While Premiere was running I killed some CFA files to free hard drive space. I couldn't kill some files because they were being used in Premiere. Thus, I presumed they weren't being used, I deleted them.
      2. Using "Export to DVD" my rate is 3.17 Mbps
      3. I have four stacked audio tracks in the timeline. They are mostly duplicate layers for increasing audio volume. Mostly small clips.
      Thoughts? Thanks
        • 1. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
          Harm Millaard Level 7
          1. Not very wise.
          2. Pretty low.
          3. Makes no sense.

          More details are welcome.
          • 2. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
            the_wine_snob Level 9
            Harm has hit the three possible problems on the head.

            Do not delete the CFA, or PEK files, until the Project is finished. If you do, do so with Premiere closed, not running. When you launch PP these files will be recreated. Clean other files from your HDD, if you need space, until your Project is finished.

            You can likely get a higher bit-rate, if you handle your Audio a bit more wisely. This bit-rate will yield pretty low quality. What is the Duration of your Project? Can you use a DL DVD for this Project, to get a higher bit-rate? Also, look into using Dolby Digital Audio, to free up a bit of space to allow a higher bit-rate for your Video. Won't be much, but might help.

            Instead of stacking your Audio files, address their volume with the Audio Mixer, the Gain control (Rt-click on the Audio Clip(s) and adjust there), or use a program like Soundbooth, or Audition to address the Volume levels.

            Hunt
            • 3. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
              Jim_Simon Level 8
              Do it again. Premiere will recreate any missing CFA files.

              Maker sure you have audio selected to be exported.
              • 4. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                Dag Norum Level 2
                Harm,

                >3. Makes no sense.

                Please explain why it does not make any sense in detail :)

                I'm going to give you a test to do before you answer. File, New, Bars and Tone, put the bars and tone on the timeline and read the Audio Master Meter when the timeline is played. Now, put the bars and tone on to the timeline again so you have two copies exactly over each other. What do you read now in he Audio Master meter?

                Dag

                Maybe some reading about two correlated and two uncorrelated sound sources mixed together giving +6 (corr) and +3 (uncorr) dB increase in volume could be interesting.
                • 5. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                  Harm Millaard Level 7
                  One master track at 100%.

                  With 1 audio track that represents 100%, with 2 audio tracks, each represents 50%, with 3 audio tracks each represents 33.3%, etc.
                  • 6. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                    Dag Norum Level 2
                    Harm,

                    I see that you now are talking about something you probably not have a clue about. Percentages are of VERY little interest when it comes to sound.

                    Did you perform the test I described?

                    The OP with four equal audio tracks on top of each other (and probably therefor correlated) will get an volume increase of +12dB.

                    Dag

                    EDIT: Do the test I described, it's educational. The test will give a 6dB increase in volume.

                    PS! In order to get a +12dB increase, you'll need to do double the amount of tracks, meaning now four tracks.
                    • 7. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                      Harm Millaard Level 7
                      Dag,

                      Thanks for the test and tip. I stand corrected. Still learning every day. I never expected that and it is completely illogical, but you are right, despite the illogical nature.
                      • 8. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                        Dag Norum Level 2
                        Harm,

                        In a linear world, yes you are right, it seems illogical.

                        But, sound is better explained in a logarithmic way (not going way into that now).

                        The funniest thing I have heard a couple of times, have been those people who have put up noise reducing fences along a road, and they say: We have reduced the noise with 20 percent.

                        Yup, 20% reduction is approx -1dB, hardly noticeable at all. 3dB or 6dB, dependent on sound power or sound level is a 100% difference (PS! in the logarithmic world, 100% is nothing more than the double, not the absolute top or maximum).

                        Anyway, thanks to you Harm for being willing to learn, that's what I like.

                        Dag
                        • 9. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                          Harm Millaard Level 7
                          Dag,

                          I know you are quite adept with audio. So a simple question, if you have an audio track where you want to increase the volume, what will give you better quality, doubling the track or increasing the audio volume in the effects panel?
                          • 10. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                            Jim_Simon Level 8
                            I had assumed that Harm's comment about making no sense was because it's just easier to increase the gain than to duplicate tracks.
                            • 11. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                              Dag Norum Level 2
                              Harm,

                              To answer in a simple way: Just do an increase in the audio volume, you probably won't notice much difference between doubling (or quadrupling) and an increasing of the volume in the effects control.

                              But, if you have a two microphone shot, I would certainly double the track because the background noise will most likely not be the same in both microphones. Hence, you'll get a +6dB increase in what's equal (correlated), but only, easily said, a +3dB in what's not equal (uncorrelated).

                              Dag

                              EDIT: I would also swap the channels in the duplicate.

                              EDIT2: Actually, the "EDIT" comment is not a "would" case, but a "have to do" case.
                              • 12. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                                Jeff Bellune Adobe Community Professional
                                >But, if you have a two microphone shot, I would certainly double the track because the background noise will most likely not be the same in both microphones. Hence, you'll get a +6dB increase in what's equal (correlated), but only, easily said, a +3dB in what's not equal (uncorrelated).
                                I would also swap the channels in the duplicate.

                                I didn't know that. I'll have to try it next time around. Thanks for the tip, Dag. :)
                                • 13. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                                  Dag Norum Level 2
                                  You are welcome Jeff!

                                  Please note a couple of things:

                                  - The volume in both channels (the two microphones) should be more or less equal. A difference in volume of 10dB (just to pick a number) makes the benefit of what is correlated to be only approx 0.2 dB, and that is basically nothing. So, a little per channel work (volume) may be required before duplicating the audio track.

                                  - Phase shift should not be occurring too much between the two microphones. The waveform should be looked at in Soundbooth (or Audition) in order to see if the "tops" are synced in time.

                                  - And, just to make it to a VERY clear point, the channels HAVE to be swapped in the duplicate in order to get the effect of what's correlated or not.

                                  *******

                                  This technique is nothing new, it has been used in many ways. Correlating signals, and amplify what's equal, or depressing what's not equal, and for en/de-crypting data (meaning mixing the original data with something "wild", and then retrieving the data by subtracting the "wild" by the means of the correlating "facts").

                                  Now I better stop :)

                                  Dag
                                  • 15. Re: Audio clips disappear when burning DVD. 48kHz 16 bit PCM
                                    Dag Norum Level 2
                                    You are welcome Harm!

                                    Enjoying my newest PC, and guess who had a couple of good tips that I used :)

                                    Dag