Jan Ozer at Streamingmedia.com has written a detailed tutorial on how to connect an external microphone to a soundboard to capture live audio.
Connecting your camcorder to an external microphone or soundboard is a critical skill for any event or corporate videographer, though it can be surprisingly challenging, making it an exercise best performed well in advance of the actual live event. In this article, I’ll walk you through the process, beginning with the assumption that your camcorder has XLR connectors and that your camcorder’s manual is handy.
First I’ll walk you through the process of connecting a microphone, then a soundboard. I’ll demonstrate connecting my Canon XH A1 to a battery-powered Azden shotgun microphone, but I’ll keep reminding you that while the procedure will be similar for most camcorders, the connections and settings will differ.
Step 1. Physically connect the microphone to the camera.
If you’re connecting two XLR inputs into the camera, this is simple: Insert the left cable into Channel 1 and the right in Channel 2. If you’re connecting a single XLR connector, typically you want the audio to flow to both tracks. Even if you’re encoding in mono, this prevents errors such as audio registering on only one side. In this case, with the XH A1, you would insert the cable into Channel 1 and use the switch shown in Figure 1 [above] to send the audio to both channels.
Overall, the two absolutely critical resources every first-timer needs are plenty of connecting and testing time and the camcorder manual close at hand. Without both of these, you’re setting yourself up for a high-stress connection session with only a fair to middling chance of success.
Read the full tutorial here.