Help needed with distorted audio

I’m helping a friend make a video to be posted on YouTube. We recorder her speaking and I mixed that audio with an audio track from a CD using Audacity 1.3.6 on Windows. The audio mixed fine and sounded fine when I added it to the video I made and posted on YouTube. Apparently, I must have had the volume low on my speakers since I didn’t hear a ton of distortion that I heard while viewing the video on a friend’s system.

So, I have loaded that audio file into Audacity 1.3.9 on Ubuntu 9.10 Linux (64-bit) but I’m not sure what the best course of action is to deal with the distortion.

Here is how the MP3 looks when loaded in Audacity 1.3.9:

I don’t know if I just need to reduce the gain or to use the “Normalize” effect or some other tool to reduce the distortion. I’m thinking all the red lines are the problem areas. :slight_smile:

Any advice? I’m new to doing this kind of work so I apologize if I’m not asking my question correctly or using the correct terminology. I can post a link to a snipet of the audio if hearing the distortion would help.

Thanks in advance!

Peace…

You’re doing everything OK, but your timing is off. When Audacity mixes down several tracks to stereo, it just adds them up. It’s not unusual at all to get a ton of overloading and clipping when that happens. You didn’t listen to the final too closely before it posted. As you’re finding out, your exported “client master” had it, too.

The easiest way to get around this is reduce all the tracks by 6dB with the amplify tool before mixdown. Then touch up the levels a bit (if needed) before delivery.

The current show is likely trash, but you can try the Amplify tool to reduce the level. You saved all the original work and Project, right?

Koz

Thanks! Yep, I’ve got the project file saved so I can go back and try this again. :slight_smile:

Peace…

<<<I’ve got the project file saved>>>

The Project File goes along with the _DATA folder. They both have to be there and all the music you imported has to be exactly where it was.

Koz

Yep, I had all those files still and was able to adjust the amplification, as you suggested.

What I did was load the “Amplify” tool and changed the default setting of 3.3 to -3.3 and exported the tracks as a MP3 file.

One thing I’m noticing is YouTube appears to be doing some kind of volume increase or adjustment on the composite video file since when I view it on YouTube, the narrative is louder than when I view it on my computer using the “Totem” movie player on Linux.

In any event, the distortion that was there is now gone. :slight_smile:

Thanks!

Peace…

YouTube has always insisted on its own format and settings. The trick is to prepare your movie so the transition is as smooth as possible.

What usually happens is someone demands to know how to compress their three-hour movie so YouTube’s time limits can be defeated. I personally would follow the YouTube instructions.

Koz

Thanks. I’m not trying to do anything fancy or try to “get over” or anything. The video we posted is original footage we shot and is just over 9 minutes long and I made it a MPEG-4 AVI file using ffmpeg (ffmpeg was used by Kino to render the video). I guess after YouTube does it’s processing of it, the volume is increased.

Throughout this project, Audacity has proven to be an invaluable and critical tool. I had never used Audacity to the extent I did for this project before so I had no idea about how powerful of a tool it really is.

Thanks again for your help!

Peace…

<<>>

What did YouTube want you to do? If you made an MPEG4 compressed show and submitted it to YouTube, then chances are, YouTube had to uncompress it and then recompress it in its own format, causing a little more damage at each step. AVI is a very old Windows format and MPEG4, unless you have other tools, defaults to a very small, low rez picture.

You need to be careful not to follow one of the hundreds of web sites telling how to submit work to the old YouTube. Look for dates. The newer YouTube has more modern compression and formats (16x9 wide screen) and is very different from the old one.

Koz