AT897 First impressions
 

1) Noticably "cleaner" sound than onboard mic (GL2)
2) Much more sensitive (hotter?) than the onboard mic. Had to turn down the mic level to about 30%(of max), compared to 70% for the onboard mic.
3) No matter how good the mic, recording in a noisy environment results in a noisy recording :(

Is there some way to power the mic with the GL2, instead of the AA battery?

I didn't particularly notice it being more sensitive than the onboard mic for either the GL2 or the XL2, but definitely agree with points 1 and 3. In my amateur opinion, you got a great mic for the price!

The GL2 doesn't supply phantom power, so you either need a battery in the AT897 or an XLR adapter that supplies it.

Funny you say that about the mic being hotter. I feel as if I can't get a good signal from my 897. I used to have it camera mounted, but I've taken it off and use it through my mixer now (read: preamp) to get a bit more umph from it. The mic sounds great and has a useful pickup pattern through. I guess the next step is to order a new Beach Tek adapter to supply phantom to it and try it once again on the camera.

Good luck!

I videotape indoor sporting events. Using the onboard mic, I found that setting the mic level 70% (of max) gave me a good recording level. When I started using the 897 I had to turn down the mic level to about 30% to keep out of the red.