Microphone Cables
YSTV's Canon XM2 and HVR-1000E cameras both ship with stereo audio connectors, yet outboard microphones (dynamics, and powered rifles) are inherently mono. We have therefor defined a wiring standard that is a little convoluted:
- stereo minijack TIP - XLR pin 2
- stereo minijack RNG - XLR pin 2
- stereo minijack SLV - XLR pin 3
- XLR pin 1 (gnd) - disconnected
This results the total hot & cold (+/-) difference across the microphone (not just + or - to gnd, which would be half the amplitude) being sent in parallel to both the left (ring) and right (tip) channels of the camera. The camera's ground line (sleeve) becomes the "cold" or "-" which is by now you know, the other side of the mic!
Why this way? we used to have a mapping of stereo sleeve = XLR 1, stereo ring = XLR 2, and stereo tip = XLR1, and stereo sleve = XLR3. This meant audio would only exist on the left channel, and be half the amplitude it could have been! This was understandably silly, and would result in people having to "fill with left" in the edit, but people would inevitably forget to do so... We then went with a T = 2, R = 3, S = 3 mapping. This made audio on both channels, both the left and right would be oppositely phased: this meant on mono systems, the audio would be cancelled out when played back, and not noticed in the edit! Then I, (Mike Chislett) discovered it and changed it to our now more sensible mapping. This means no more Fill with left, and no more phase issues! Yey! Happy days.
