Is there a way to use both the onboard mic (lets say on channel 1) and another mic through the MA-100 (maybe on channel 2) at the same time? Or, am I limited to only inputting the mics or only using the onboard? It seems like I should be able to do both, but I can't figure it out. Any help would be appreciated!

Annie Cheatham

You can do both since you have the MA-100. You would have to set the audio to 12-bit 4 channel where the onboard mic uses 2 channels since it is stereo and use the other two channels for your other sources.

Yes, you set the camera for 12 bit audio mode and run the audio in on 'Audio 2' keeping the main mic where it is.

Be aware that you will not be able to listen to audio while recording without selecting it via the 'audio monitor' button the left side of the camera. You have 3 soft postions: ST-1, ST-2, and mix. Via the remote controller you can select how much of the two channels are mixed in the headset channel. This does not affect the recording level, only the audio in the mix position. By toggling between ST-1 and ST-2 you can use the meter to set the true audio level.

The definitive article IMHO on XL1 audio is available a number of places. Below is where I've bookmarked it. You may want to as well:
http://www.equipmentemporium.com/xl1_audio.htm
It's available in 4 parts right here on the Watchdog:
http://www.dvinfo.net/canon/articles.php#audio

As other's have said, you can do what you want by using the 4 channel capability of the camera. However, the DV standard requires audio to be 12-bit (instead of 16-bit) in 4 channel audio format.

If you must use 16-bit audio, then you'll need to use a mic plugged into the MA-100 instead of the built-in mic and configure the audio mode as per the article above.