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Sakuya
13th August 2004, 01:16
For the duration of this forum's downtime, I have had an audio problem where most people can't help me. Hopefully, the people here can. I have an AC3 5.1 audio file. When I burn it to DVD, the background music on my home entertainment system gets really soft while the voices and the sound effects are loud. I know this is not normal. Somebody recommended that I either downmix it to AC3 2.0 or edit the individual tracks in Soft Encode. So I did that. I opened it in Soft Encode as Dolby Digital (decode as PCM). That listed 6 different wavelengths, one for each channel (as follows):

FL: Sound Effects, Music
C: Voice
FR: Sound Effects, Music
SR: Sound Effects (faint)
SL: Sound Effects (faint)
LFE: Bass

Here is some stream informaton produced by Soft Encode on the original AC3 stream if it's of any use:

Audio Coding Mode: 3/2 (L, C, R, l, r) LFE
Bit Stream Mode: Main Audio Service; Complete Main
Dialog Normalization: -27dB
Data rate: 448 kbps
Surround Mix: -3dB
Center Mix: -3dB

I have tried it with these settings and then burned to DVD. The music is much louder but the explosions no longer have the original "oomph" and the surround is no longer as impressive:

FL: 11dB
C: Unchanged 0dB
FR: 11dB
SL: Unchanged 0dB
SR: Unchanged 0dB
LFE: Unchanged 0dB

Then I tried using these settings below. I increased the rear speakers because it lost its surround. I also increased the bass. Even with the LFE set at 1.5dB, during one of the explosion scenes, I think there was a slight clipping.

FL: 12dB
C: Unchanged 0dB
FR: 12dB
SL: 4dB
SR: 4dB
LFE: 1.5dB

I'm still not sure if this is correct or not. Is there a way to tamper with the settings in order to get a more professional and standard surround sound along with increased volume for the background music? What I have produced sounds pretty amateurish and sounds like it's missing something.

Eye of Horus
13th August 2004, 13:30
Originally posted by Sakuya
For the duration of this forum's downtime, I have had an audio problem where most people can't help me. Hopefully, the people here can. I have an AC3 5.1 audio file. When I burn it to DVD, the background music on my home entertainment system gets really soft while the voices and the sound effects are loud. I know this is not normal. Somebody recommended that I either downmix it to AC3 2.0 or edit the individual tracks in Soft Encode. So I did that. I opened it in Soft Encode as Dolby Digital (decode as PCM). That listed 6 different wavelengths, one for each channel (as follows):

FL: Sound Effects, Music
C: Voice
FR: Sound Effects, Music
SR: Sound Effects (faint)
SL: Sound Effects (faint)
LFE: Bass

Here is some stream informaton produced by Soft Encode on the original AC3 stream if it's of any use:

Audio Coding Mode: 3/2 (L, C, R, l, r) LFE
Bit Stream Mode: Main Audio Service; Complete Main
Dialog Normalization: -27dB
Data rate: 448 kbps
Surround Mix: -3dB
Center Mix: -3dB

I have tried it with these settings and then burned to DVD. The music is much louder but the explosions no longer have the original "oomph" and the surround is no longer as impressive:

FL: 11dB
C: Unchanged 0dB
FR: 11dB
SL: Unchanged 0dB
SR: Unchanged 0dB
LFE: Unchanged 0dB

Then I tried using these settings below. I increased the rear speakers because it lost its surround. I also increased the bass. Even with the LFE set at 1.5dB, during one of the explosion scenes, I think there was a slight clipping.

FL: 12dB
C: Unchanged 0dB
FR: 12dB
SL: 4dB
SR: 4dB
LFE: 1.5dB

I'm still not sure if this is correct or not. Is there a way to tamper with the settings in order to get a more professional and standard surround sound along with increased volume for the background music? What I have produced sounds pretty amateurish and sounds like it's missing something.

What you lose in the new AC3 is this :
You decode to 6 mono Wavs and then encode again.
You will lose important information because you will re-encode material that was already encoded.
It's the same like converting an MP3 to WAV and re-encode with a different (higher) bitrate : it will only get worse !!

You can only get good results when you have access to the ORIGINAL 6 mono wavs !

EoH

Sakuya
13th August 2004, 20:48
How do I do that? :(

E-Male
16th August 2004, 22:23
i think the problem is that with standart options softencode will reduce the volume of the rears by 3db and do some other stuff to the audio
it doesn't just encode it