Noob question

1. Thanks all for replies. Turns out the f6 was set to record 4 tracks as described and I just deleted the ones I didn't want. Called 'poly' mode and there's also 'mono/stereo' mode. 

We can't tell you. You need to look at the way the F6 is set up to determine exactly what is being recorded on each track, but on the face of it, it sounds as though the two tracks with differences would be the ones recorded by mics that weren't immediately adjacent to each other. I'm putting it like that, because it's not really 'stereo' unless you set the mics specifically to record an accurate stereo field - what you've got would probably better be described as an ambient recording rather than stereo per se.

The best answer to this though is to listen to the results - I think that's the best way you'll find exactly what you've got.

Could you tell us how the F6 was set up and how many trackes were recorded.