I understand the audio input 1, but I'm confused with input 2. Input 1 allows you to record to one of the two available channels of audio or both simultaneously. Input 2 is confusing as I'm assuming it allows you to record audio to channels 3 and 4 in 32K mode. But there is no selection for which channel you want the signal to record to. Not to be picky, but shouldn't there be 4 xlr connectors? What am I missing? I'm sure I'm not thinking this through right.

Channel 1 can be sent to channel 1 and 2 or channel 1 only.

Channel 2 can only be sent to channel 2.

Ok. So where's channels 3 and 4?

Channels 3 and 4 are in your video editing program....

like Premiere Pro...

Huh? DV allow 4 channels of simultaneous audio at 32k. At 48K there are only 2. The reason I'm asking is that Premier Pro treats the first two channels like stereo and places them together on the timeline. That's impossible to edit if one of the tracks comes from the on camera mike and the other from a wireless or line in. Of course, Avid places the two on separate tracks, but I mostly edit in Premier as I'm comfortable with it. The XL1's mic is stereo (sort of) and uses the first 2 channels, but with an adapter, you can add two more imputs for channels 3 and 4 which is where I put the wireless. Those channels can be captured separately. So again, how does the Pd-170 capture the other two channels? There is a selection in the menu for 48 and 32 audio as well as a display in the viewfinder for the other two channels.

The Sony definitely will not allow 4 simultaneous channels. Inputs 1 & 2 are mono-only. The line connectors on the side of the camera are line-out during camcorder operations.

Look in your owners manual and you should find the directions for recording the 3rd and 4th channels in a separate operation.

Thank you. Now I know.

OK you can separate the two audio channels into mono left and right in Premier.