Sound Devices 702
 

I just received my Sound Devices 702 ENG recorder. After owning a couple of field recorders from Tascam and Fostex, I gotta say I don't know why I wasted my money on those other recorders. The 702 is a true gem, albeit a bit expensive, but, well worth the cost. I'm not too familiar with syncing a video camera with an external recorder, other than using a clapboard.

Is there any easy way to sync the black burst signal from the composite video output to a word clock on the audio recorder?

Congratulations on you new toy! Santa was good to you this year. Do you have the 702 or the 702T?

the 702. i decided that the 702T doesn't help my syncing by adding a timecode unless i could sync the audio recorder timecode simultaneously with the cam. the clapper technique works fine and the streams stay in sync very well. since the 7 series recorders are 1394 aware, seems like the 702 software could incorporate a "record" signal from the camera

So why the interest in syncing to blackburst from the camera then? AFAIK, all that would do would be insure the sample rate of the recorder is slaved to the camera so sound and picture wouldn't drift out of sync over the course of a shot, but since they're already staying in acceptable sync, why bother? My reading of the 702's manual doesn't mention that it accepts blackburst so my guess is you'd need an external device that derives word clock from composite video or blackburst. The MOTU Digital Timepiece would do it, for example, but it's pricey and not very practical for field use.

My effort to date has been fairly short clips, less than 20 mins. I'm concerned that over a longer time, like 1-2 hrs, I'll see more of an audio sync drift. I really can't do the clapper thing every hour, the talent probably won't like that. So, I was looking for an automated method, like the MOTU unit, but, cheaper and portable...LOL. Well, I can ask, can't I?

Thanx for your help

The better NLEs offer time stretch or compression for audio without distorting it. If the tail has drifted out of synch by a few frames, a minor adjustment should be possible without creating too many headaches. Single shots that long would be fairly rare anyway, wouldn't they?

yeah, ultimately, that's the method I use to sync the two together. not really a bad approach, except for the time it takes to cue up the video and audio streams, sync the head, then the tails. I wanted to find a more automated method, but, it seems it's not to be had, at least not inexpensively. I think what I'll do is feed my external audio recorder thru the cam. then I can sync the waveforms from the two audio streams.

I don't think I'd do that. Sending audio from the mixer to the camera and then to the recorder seems to defeat the purpose of spending on the high quality audio circuits in the Sound Devices recorder since it will have already been subject to degradation by going through the lower quality circuits in the camera. And it won't get the clocks in sync anyway. Far easier to just do a tail-slate as well as the normal head-slate on those longer shots where you think it might be an issue. If you do want to record the audio on both the tape in camera and the SD702, I'd at least make sure the SD was upstream of the camera. Even better, use a mixer with 2 pairs of line outs - feed one to the SD and the other to the camera.

Steve...

thanx. I had assumed the audio out would be a pass-thru, not a real compressed/uncompressed version. I like your idea with the mixer, think I'll give that a try. I, usually, mix the signal from the musician's soundboard in my own mixer anyway. in fact, maybe what i want to do is run the feed from the kick drum thru an aux send into my camera. That's a pretty good beat signal.

I wasn't even think of compression. Most cameras audio circuits are marginal at best, certainly nowhere near the high quality of your SD recorder's preamps etc.

The option of running from recorder to camera probably exists. I've got a 744T, but I imagine that the 702 has a tape out jack or some other out that you could run to the camera. Steve's concerns are valid about not getting the camera anywhere near your path for recording decent audio, but once you've got it, having a reference on the camera doesn't hurt.

Hey Bill, I notice you're up in Santa Fe. Always nice to see a fellow New Mexican on the boards.

Like it's Old Home Week - I grew up in Albuquerque, graduated from Sandia High back when Jonah wasa deckhand and UNM in '74

Wow, it really is a small world. I did a shoot over at Sandia High just last year as part of a PSA on truancy. It's still there :)

sheesh...great to hear all you folks here in ABQ. I live in Sfe but work in ABQ. At least, that's tru today. Yesterday, I spent the day playing with my 702.....what a great snowstorm, huh?

I recorded Chris Dracup over at a place on central with a Fostex MR8. The dynamic range of a 16 bit recorder just kept clipping the peaks or swallowing the lows. Did a disservice to some very good jazz. I think this 24 bit recorder oughta help that prob.

...yep, could connect the headphone out to the camera...funny I didn't think of that....course, I'd want to monitor A/B not A/Bm....LOL

Good to know the old place still stands. Us science-fair types left Sandia with a bang when we graduated in '62...literally. 3 major loudness but undamaging explosions marked our last day in the chem lab <grin>. Like I said, no damage was done but I do think that was the last year they let students get ahold of keys to the chem and physics lab stockrooms. Oh, and the vodka gimlets we made by distilling some fermented glucose we happened upon, combined with some citric acid, might have had something to do with that as well. Great way to pass the time in a boring lecture. LOL