5.1 audio question with Homework Results
gold
wrote on 1/14/2004, 6:29 AM
Comments
craftech
wrote on 1/14/2004, 7:02 AM
Gold,
You should post it here. I am copying it and pasting it for you.
John
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This was my first attempt at 5.1 and so its a newbee question. I am using two products from 2 different vendors so this is not a pure question and I will do more investigation to localize the problem, but one of you may know the answer immediately, so I am posting now with apology for not doing my homework first [slap of knuckles with ruler heard on back speakers].
I captured a multiplexed video (raw file is mpeg2 video and mpeg1 layer 2 audio) file from an old hi8 auditorium type source since it would allow putting applause in back and sound to stage and sides of auditorium as the action moved about.
Then I imported the multiplexed video/audio into a Vegas 4.0 5.1 project with the intent of converting the stereo to 5.1 and exporting it as an AC3 file. I duplicated the audio track and changed the duplicate to LFE to get the .1 channel. I used the panner and set key frame surround points of the HOLD type at points where the action moved [example: at beginning of applause moved diamond to back center, at end of applause moved the diamond to front center creating two red diamonds on the center [surround envelope] time line. Playing it back in Vegas but with only 2 speakers [one of my homework assignments is to hook up 2 rear ones laying on the floor nearby so that I can hear 4 channels to the Audigy ex card] the faders showed the sound moving correctly from front to rear and back to front.
First I exported it as was (which gave only the front speakers). Then I rendered it using the 5.1 audio template and set the amplitude to -1 dB [another question, what should this be -29dB?]. Then I exported it as an AC3.
This is where I switched programs. Then I imported the mulyiplexed video and the two AC3 audios into Encore and removed the mpeg1layer2 audio and made two play buttons--one with the video and the first ac3 audio and the second with the video and the second [rendered] ac3 audio and burned a dvd. Note: I can try a number of sound options this way on a single dvd.
In a standalone player with a dolby 5.1 surround system and speakers--a home theatre arrangement, the first button played only the front channels with silence for the applause as expected. However, the second played full surround but the front and rear were reversed: dialog came from the rear and applause from the front. Front and rear are correct on purchased dvds.
Any thoughts other than localize the problem, which will be my next step. Thanks in advance.
Gold
You should post it here. I am copying it and pasting it for you.
John
-----------------------------------------------------------------------------
This was my first attempt at 5.1 and so its a newbee question. I am using two products from 2 different vendors so this is not a pure question and I will do more investigation to localize the problem, but one of you may know the answer immediately, so I am posting now with apology for not doing my homework first [slap of knuckles with ruler heard on back speakers].
I captured a multiplexed video (raw file is mpeg2 video and mpeg1 layer 2 audio) file from an old hi8 auditorium type source since it would allow putting applause in back and sound to stage and sides of auditorium as the action moved about.
Then I imported the multiplexed video/audio into a Vegas 4.0 5.1 project with the intent of converting the stereo to 5.1 and exporting it as an AC3 file. I duplicated the audio track and changed the duplicate to LFE to get the .1 channel. I used the panner and set key frame surround points of the HOLD type at points where the action moved [example: at beginning of applause moved diamond to back center, at end of applause moved the diamond to front center creating two red diamonds on the center [surround envelope] time line. Playing it back in Vegas but with only 2 speakers [one of my homework assignments is to hook up 2 rear ones laying on the floor nearby so that I can hear 4 channels to the Audigy ex card] the faders showed the sound moving correctly from front to rear and back to front.
First I exported it as was (which gave only the front speakers). Then I rendered it using the 5.1 audio template and set the amplitude to -1 dB [another question, what should this be -29dB?]. Then I exported it as an AC3.
This is where I switched programs. Then I imported the mulyiplexed video and the two AC3 audios into Encore and removed the mpeg1layer2 audio and made two play buttons--one with the video and the first ac3 audio and the second with the video and the second [rendered] ac3 audio and burned a dvd. Note: I can try a number of sound options this way on a single dvd.
In a standalone player with a dolby 5.1 surround system and speakers--a home theatre arrangement, the first button played only the front channels with silence for the applause as expected. However, the second played full surround but the front and rear were reversed: dialog came from the rear and applause from the front. Front and rear are correct on purchased dvds.
Any thoughts other than localize the problem, which will be my next step. Thanks in advance.
Gold
craftech
wrote on 1/14/2004, 7:31 AM
I am not sure what you did, but here are some posibilities:
1. If you monitored panning with the grid and a monitoring system, the grid will be off if you don't have the monitoring system set up properly.
2. If you keyframed muting (channels or gain) using the center channel fader it won't work.
3. If you moved events along the timeline, the keyframes won't move with it unless you check off Lock Envelopes to Events from the Options menu.
4. Encore may have a different requirement for the file format of the LFE channel.
5. You have too many variables in that an answer may require a person who knows both Vegas and Encore really well.
6. Hopefully this isn't the typical high school or college assignment which was put off until last minute
John
1. If you monitored panning with the grid and a monitoring system, the grid will be off if you don't have the monitoring system set up properly.
2. If you keyframed muting (channels or gain) using the center channel fader it won't work.
3. If you moved events along the timeline, the keyframes won't move with it unless you check off Lock Envelopes to Events from the Options menu.
4. Encore may have a different requirement for the file format of the LFE channel.
5. You have too many variables in that an answer may require a person who knows both Vegas and Encore really well.
6. Hopefully this isn't the typical high school or college assignment which was put off until last minute
John
gold
wrote on 1/14/2004, 8:01 AM
craftech
wrote on 1/14/2004, 8:16 AM
Thoughts on the db level?
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If you are referring to dialog normalization set it to -31db if you want full volume.
John
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If you are referring to dialog normalization set it to -31db if you want full volume.
John