Require Help with AC3 Filter Settings for Perfect WAV Convt.

[MikeL2k]

Hi. I am in the process of converting an XvID video with 5.1 AC3 sound and have downloaded the AC3 filter but am unsure and having some problems with the settings. The default settings resulted in my sound being very low, so I had to raise some of the settings, but I am afraid that I might not attain the best sound unless I set certain settings at certain spots.

My question is, does anyone have a good configuration of what settings to use / select / mark to achieve a "Perfect" conversion from AC3 to WAV, so I retain the sound in it's highest quality without any sound loss. I tried converting already and since I didn't know the settings had an effect on the sound, my converted AC3 > Wav file is very low, so I need to find out what is the best settings to use in the AC3 Filter config to make sure my audio comes out sounding perfect.

Also, I'm unsure what some settings do, especially under the "Mixer" tab like... Audio Gain Control, One-Pass normalize, and Auto Matrix.

The version of AC3 filter I am using is AC3 Filter v0.70b by Vigovsky Alexander (website: http://ac3filter.sourceforge.net)

Any help would be soo helpful, thank you.
Mike

P.S. Not sure if it helps, but the converted Wav file will be added to a VCD, so it's a AC3 > Wav > VCD conversion.

[MikeL2k]

I think I discovered a good setting. I saw quite a few looks on this topic since I posted it so I thought I would share my findings in case anyone else was wondering also.

In AC3 Filter I used the following options to achieve great conversion.

Under Output > Speakers I selected Dolby Surround/ProLogic. This setting compacts the digital surround sound into 2 channels, so you still retain all the great surround sound and only need 2 speakers, plus using a Dolby/ProLogic decoder/speakers should allow for the full surround wanted, not quite as good as 5.1, but if you don't have a 5.1 decoder ProLogic is a good alternative.

If you are converting to a VCD, then under Output > Sample format choose PCM 16bit.

Next, it is wise to unselect the "Use DRC" box under DRC. If this option is enabled it will ultimately ruin your audio experience, by adjusting the sound levels. If you're doing a backup of say a movie epic like Lord of the Rings, with lots of intense orchestra music and high and low sounds then you definitely don't want this option on. What DRC does, is it enhances the lower and louder background sounds, and epics usually have lots of these. For instance, say at one point, the movie is showing a big battle and the music is nice and loud then all of a sudden the volume is lowered so you can hear more of the voices talking or of the sound FX, this option can enhance it too much causing certain sounds to almost be muted.

Next, you may want to save these settings in the preset box so next time you can easily select the option to switch back to these settings quickly.

Now click on the "Mixer" tab. If your audio in the video seems to be too low and you need to turn up the volume then under Gains > Master, raise the bar up slightly. I tend to use the box and enter an amount rather then use the bar as this is more accurate. To get a good amount of extra volume without overflowing, try just entering 10. This is a good amount and shouldn't cause overflow, if still to low keep increasing by 1 until you are satisfied.

Now under Gains > LFE Voice and Surround, uncheck the boxes to enable the fields. Try entering 3 for each option. This enhances the 3 parts of your audio (Voices, Background Sounds and LFE which is your Sub Woofer noise) where it's needed most. Don't go overboard, as 1 number too high can cause overflow fast and then your sound will start to contain static and could begin to bleed.

Under Options, make sure only Auto Matrix is selected. Uncheck the others. If you raise the numbers higher then 3 on the last step, then you may want to check Auto gain control which will help keep the loud sounds in check. Also make sure normalize is unselected too as it can also have some of the same effects as the DRC, I only recommend this option if the audio in your video likes to play musical chairs and get real loud when the music starts then real low when the voices start.

And that's about it... Go back to the Main tab and save your preset then click ok and reopen your video and try it out.

Hope that helps.

[johns0]

Just run the wav or ac3 file thru besweet with gui and choose pregain normalize to 100% and save as mp2.

[MikeL2k]

I tried that method and the sound didn't come out that good for me, it sounded about as good as a 112kbps MP3 but with a good ammount of pop and clicks. I found that the method I used worked amazingly well so much so I almost couldn't tell the difference from the final VCD file and the AC3 file.

But thanks for the info.