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  1. Member
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    I'm already using DGIndex and ImagoMPEG-Muxer to help fix errors in the clips I'm taking off DVDs, so I now always go through a step where I've got the audio all on its own. What's the easiest way to convert it to wav, amplify it, and convert it back to whatever format it was before, and will it all still be in sync after this is done?

    (Background info: the clips come from recodings made on an ancient Philips-system VCR, copied to VHS 34 years ago, then copied to DVD ten years ago with the DVD recorder set to HQ and there was no way to control the volume during those copying steps.)
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  2. They sound low after being uploaded to YouTube as well? Not just on the computer?

    Anyway, one way is to demux the audio and video (DGIndex, as you learned yesterday) or just take the audio before remuxing with ImagoMPEG-Muxer. Convert it to WAV audio if necessary (I use BeSweet for that although there are many ways (HeadAC3he, eac3to, etc.). Open it in a WAVE editor (I use Audacity). Raise the volume ('Amplify' in the 'Effect' list). Save it, convert it back to what it was before and then remux.
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  3. Member
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    Thanks again, manono,

    Yes, they're ridiculously quiet everywhere, including on YouTube. I wrestled with BeSweet for a time and eventually managed to work out how to do everything - Audacity offered a 29dB amplification and that's brought it up to the proper level. Now I'll have to go through the same process with all the other clips and replace the ones I've already put on YouTube.

    The reviews on the BeSweet download page suggest that a lot of people never manage to work out how to use the tool, so I'll describe the process in case it helps other people who find this and need to do the same thing. The main difficulty I had to start with was that Windows Media Player decided it had a claim on the audio file after demuxing and refused to tell me what kind of file it was beyond the description, "movie clip"! I found a way to tell it to get lost by going into "properties" and temporarily changing the program associatied with the file to VLC, and that revealed the file to be .mp2. Armed with that information, I was finally able to work out how to get BeSweet to find the file. The next difficulty was getting it to select the filetype for the output, but I eventually found the right place to set that underneath the button with "save" on it, and after a failed attempt with the wrong wav setting (which created a file of crackle), I set it to PCM (WAVE/AIFF) and it produced a perfect wave file. The rest was easy, converting the amplified version of the wav file back into mp2 before remuxing.

    So, thanks again for your help and to everyone behind this fantastic forum - hopefully I've got all the right tools now and can get everything done.
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  4. Yes, BeSweet can be a pain to get the hang of. Maybe I should have suggested HeadAC3he first as it's real easy. Or AoA Audio Extractor because you open the video and no matter the audio, it can extract it as WAV audio. But I think one of your main problems is that you don't have your extensions turned on. I first noticed that in your picture in your earlier post. You're crippling yourself by not knowing what kind of files you have. If interested, maybe this will help you in the future to immediately know what kind of audio (or video or any other kind of file) you're dealing with:

    http://windows.microsoft.com/en-us/windows/show-hide-file-name-extensions#show-hide-fi...ions=windows-7
    or:
    http://www.laptopmag.com/articles/show-file-extensions

    Also, I don't boost volume to the very top (the 29 you mentioned), but a bit lower. I make mine -3.2 from the top or roughly 26 for your example. Your 29 is the point at which it begins to clip and I keep it a bit lower than that. Just for future reference. Maybe others will disagree.
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  5. I think you make life harder than it is.

    If you ended up using DGIndex and ImagoMPEG-Muxer to make cuts you can open .mpg/.vob directly in Audacity (with FFMpeg installed). And if it's for Youtube upload there's no need to keep mp2 -actually the recommend audio codec is AAC-LC. Or use AC3. And you could try Effect -> Normalize to boost your audio in Audacity. And you could use MKVMergeGUI(/MKVtoolNix) to replace the audio track in your "cuts".
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  6. Member
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    Search Comp PM
    glad you figured your way thru it

    i have found Audacity to be the best tool for me on the occasions that i work on demuxed audio
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  7. Member
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    Thanks again, Manono. I'm using an XP machine for most of this (which has never been online and therefore still runs like lightning), but the Windows 7 method was nearly the same (with XP it's Control panel >> Folder options >> View >> Hide extensions for known file types).

    The 29dB amplification still left the wave some way clear of the top and bottom, so there's no danger of clipping. Normally in audacity one part will just kiss the edge after the suggested amplification has been applied, but if that sound is high frequency it will be much louder for the same amount of speaker displacement due to the higher speed of speaker movement. I don't know why it stopped short of the edge this time as there was no click anywhere reaching the edge, but it was just about where I wanted it anyway.

    Hi Videobruger - I probably should be using normalise rather than amplify as that ought to do a better job of setting the right amplification for the actual volume (without being misled if there are no low-frequency sounds present). I plan to put all the clips back onto DVD as well as uploading some of them to Youtube, and I'll also make them available to other people who may want to put some of them on DVD - they were recorded incorrectly on DVD before and only worked on a few machines, but the new versions should work everywhere. The sound was also set too low with the result that the TV volume had to be turned way up for them, so that'll be fixed now too.

    Thanks theewizard - I'm glad Audacity's a suitable tool for this task as I already know it well from digitising old audio tapes. The video clips I'm dealing with at the moment are Christmas Carols sung by a school choir (of unusually high quality), so I'll save the soundtracks as MP3 as well while I'm doing all this. One of the soloists went on to be an opera singer https://www.youtube.com/watch?v=8xa7cOjBT_0 - that clip illustrates how the volume's set too low, so I'll be replacing it with a new version soon. They all have a fair bit of hiss on them, but that can't be helped, and it isn't too bad if you plug in decent speakers.
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  8. They all have a fair bit of hiss on them, but that can't be helped
    Perhaps try Effect -> Noise Removal in Audacity. Example attached.
    Image Attached Files
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  9. Member
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    Dec 2015
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    Search Comp PM
    Thanks Videobruger for going to so much trouble over that. I experimented with that last night, but even with the slider at the left end where it hardly dulls the music at all (and does a startlingly good job of removing the hiss), it still introduces too much weird noise that conflicts with the music. It's an impressive tool, but perhaps not yet right for use on music. I'm sure it'll be possible to do it perfectly in the future when AGI can "manually" eliminate every hint of introduced hiss, though the original recording was made outside where there was a lot of background noise of the wind in the trees, and that should be retained for atmosphere. In the meantime, plugging in a pair of big speakers damps the hiss quite well and seems to be the best compromise.
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