Audio Tuning
Before we begin the relatively easy process of setting the correct volume level for your audio, let me say a few words about your audio connection. Oftentimes people who use a capture card will connect the audio cables from the external source (e.g. VCR) to the port on the back of the video capture card. This is not the best way to hook up the audio. Instead of plugging the audio cable into the port on your capture card, plug the cable into the "Line-in" jack found on the back of your sound card. By connecting the audio cables directly to your sound card, you remove the middle man (capture card) and thus increase the quality of your audio.
Setting the Correct Volume Level
If you use a volume level that is too low, the sound will be difficult to hear and the quality will be lower. On the other hand, if you set the volume level too high, you will create what is called "clipping". Clipping is what happens when a sound is beyond the volume range that your computer can handle. It doesn't sound good.
Therefore, our goal will be to set a volume level that is as high as you can make it without introducing clipping. Before we begin, make sure your video source is hooked up to your computer and ready to go. Now follow these steps:
1) In VirtualDub, enter the capture mode (File -> Capture AVI) and click on Audio -> Volume meter. You should see a window like this appear:
2) Now press play on your source video device (e.g. the VCR). You should see the volume meter react to the sound of the video.
3) Find one of the louder parts of your video. This might occur when the characters are shouting or there is loud background music.
4) Adjust the volume control so that the maximum volume reached during the loud scene is about 2/3 to 3/4 of the length of the volume meter.
5) Watch your video for another minute or two to ensure that the volume level never reaches the right end of the meter. If it does, lower the volume level a little bit more.
You are now prepared to go to my Video Capture Overview page.