I have a Canon GL2 mini DV camera over here in Baghdad. The Canon adapter that goes on the top has an attachment for a shotgun microphone on two, with two XLR inputs. So, I bought a cable that splits the one output from the mic and puts it into the R and L channels. Is there any benefit to doing this? Or should I just have it record on one channel and duplicate it during post-production?

Secondly, the overall recording level goes down when I put on my shotgun mic versus my on-camera mic. Is there a way that I can test which would give me better sound- the on-camera or the shotgun mic? I turn up the gain on the camera when I have the shotgun on there. But during playback, the sound from the shotgun sounds quieter than the on-camera. I can’t tell if it is better sound because I'm just playing it back on the camera. How would I know? Maybe I should play it back on a television.

The shotgun that I have is an Azden SGX-1 or something like that.

Mark,
Do you have a way to monitor the recording/playback with headphones?
The azden is quite likely lower sensitivity than your GL is, but shouldn't be by much. The GL has adjustable gain, have you tried balancing that?
You don't gain, nor lose anything by recording a mono signal to two channels. But it is indeed possible you've got a phasing problem due to the splitting cable, try using only one half of the cable. That also could cure the apparently low output.

The SGM-1X does have a slightly lower output compared to most of the other shotguns commonly mentioned on this board. More importantly, it does not seem to be a good impedance match for Canon's MA300 XLR adapter, which it sounds like you have there.

Jeff Toogood (see his recent posts on this) had the same experience with the SGM-1X going through an MA300. He found that he could record with a stronger imput signal by plugging the mic directly into the camera with an XLR to minijack adapter cord.

But I don't get why it should sound quieter on playback if you equalized the recording levels with the audio switch in manual mode.

Thanks for the info.

I will go back to my single cable / single jack and see what that does.

This is an odd situation because sometimes I'll be recording things, with a lower level and then suddenly a helicopter will fly over and max-out the metering bars.

I have definitely learned the criticality of watching your dalies and getting help as soon as possible before the next shot.