Sound Devices 702 or 702T?

T

tirapell

Active member
For HDSLR productions with dual system recording, is there any advantage to the 702T versus the 702 (without timecode)?

I've done quite a bit of searching and haven't been able to come up with anything definitive. I know some people may use the 702T for versitility and the ability to do higher end projects, but I wasn't sure if there was any advantage to spending an extra $600-700 if you strictly want to do dual system with HDSLR (or comparable) footage.

Thanks in advance.
 
I have a 702T. I sync it with a timecode box. I plug that timecode box into the DSLR as an analog audio signal.

Avid can decode that signal, figure out the timecode and automatically sync my dual system sound.

http://www.youtube.com/watch?v=U6m1vNTeRso

So for me 702T is worth it because I get automatic syncing. On the other hand most folks don't know that an editing program can read timecode from an analog audio track so they don't know to use this trick.

Bruce Allen
www.boacinema.com
 
bruceallen said:
I have a 702T. I sync it with a timecode box. I plug that timecode box into the DSLR as an analog audio signal.

Avid can decode that signal, figure out the timecode and automatically sync my dual system sound.

http://www.youtube.com/watch?v=U6m1vNTeRso

So for me 702T is worth it because I get automatic syncing. On the other hand most folks don't know that an editing program can read timecode from an analog audio track so they don't know to use this trick.

Bruce Allen
www.boacinema.com
Click to expand...

Bruce, thanks. Could you give me an example of a "timecode box" and what that might run cost-wise?

Does this mean that the HDSLR and the recorder have to be physically connected during the recording?
 
Bumping this, Id love to know how to get Timecode on a DSLR! What "timecode box" options are there?
 
The Denecke SB-3 is a standard. Costs about $500
There are most expensive options as well but an accurate clock is going to cost some money.

There are other iPhone/iPad app's that claim to be accurate but the fact that they are using
the electronics in those devices to keep the time they can only be so close.

If you are using the iPad for script notes or estimates it could be an inexpensive option.
For the purposes of keeping frame accurate time for 5+ hours to sync audio I suggest to not try to cheap out.
It wont be worth it in the long run.
 
Reading the first post the OP uses the words "Strictly with DSLR's"
so going by those words I don't think it would be worth going with the 702T since there are other viable options
to sync audio such as plural eyes.

If the word "strictly" wasn't used I would recommend getting the time code version
to cover yourself when you do get a job that requires it.
 
It's hard to say you will only ever work with DSLR's. If you can swing the timecode version, get it. You'll get a call one day where you may be working with a Red or Alexa, and you'll be glad you have that timecode.
 
bruceallen said:
I have a 702T. I sync it with a timecode box. I plug that timecode box into the DSLR as an analog audio signal.

Avid can decode that signal, figure out the timecode and automatically sync my dual system sound.

http://www.youtube.com/watch?v=U6m1vNTeRso

So for me 702T is worth it because I get automatic syncing. On the other hand most folks don't know that an editing program can read timecode from an analog audio track so they don't know to use this trick.

Bruce Allen
www.boacinema.com
Click to expand...

Rippie said:
Reading the first post the OP uses the words "Strictly with DSLR's"
so going by those words I don't think it would be worth going with the 702T since there are other viable options
to sync audio such as plural eyes.

If the word "strictly" wasn't used I would recommend getting the time code version
to cover yourself when you do get a job that requires it.
Click to expand...
I was more referring to Bruce's statement that there was a way to get timecode data embedded in an audio track fed directly into a DSLR that can later be read in post and sync'd with my SD 702T audio.
 
ben_r_ said:
I was more referring to Bruce's statement that there was a way to get timecode data embedded in an audio track fed directly into a DSLR that can later be read in post and sync'd with my SD 702T audio.
Click to expand...
Linear timecode (which is what we're talking about here) is actually encoded as a pulse-modulated audio signal, similar in principle to that of an old-fashioned acoustic modem. Any timecode device with a "TC Out" terminal sends it in that format and it can be recorded to an audio track by any conventional recorder like any other audio signal. Whether your editing software can decode and use that audio track depends on the software you have.

In video, one of the classic workflows is audio slaves to video. So your camera generates the timecode and records it as VITC in with the video. At the same time, it outputs the same code as LTC audio and sends it over to the audio recorder. In the audio recorder the LTC is recorded on one channel of a stereo track while the audio (mono) is recorded on the other. In post you drop the video into the timeline so that the embedded VITC aligns to the project timeline. Then you drop in the audio file and if the NLE can read the timecode channel, it positions it in the project where the recorded LTC matches the code on the project timeline. Since the mono actual audio channel is locked to the LTC channel this also positions the desired audio in sync with the video. Lock the audio and video tracks together, delete the LTC track, and you're done syncing. Obviously this doesn't work with a DSLR because it doesn't generate and output timecode.

The HDSLR situation would be a variation on this workflow. The recorder would generate timecode and send it to the camera's mic input to be recorded in lieu of actual audio. Over in the recorder, the timecode coinciding with the first audio sample is stamped into the audio file header. As the shot proceeds, the audio recorder's timecode is continuously sent to the camera and recorded there as the audio track alongside the video. In post, you'd drop the combined video/TC audio file into the project, aligning the embedded audio TC to the project's timeline, again assuming your editing software can decode the TC in the audio track. Drop in the audio file from the recorder and the NLE positions it on the project timeline according to the timecode timestamp embedded in the file header. Mute the TC track associated with the video track, lock the audio track from the external recorder to the video, and you're synced.

Another possible timecode workflow with an HDSLR would be to use a classic filmstyle smart-slate. The audio recorder serves as the timecode master. A smart-slate that displays TC is jammed with it so the timecode clock in the audio recorder and running on the slate are identical. The slate is photographed as you start to roll. The audio recorder's timecode goes into the file header timestamp. To sync in post you drop the video track into the editor and adjust the project timeline's timecode so it matches the code visible frame by frame on the photographed image on the slate. Then you drop in the audio file, letting the software position in on the timeline, aligning the embedded timestamp in the file header with the project timeline code. Voila! you're in sync. Replace the scratch audio originally recorded in the camera with the audio from the externally recorded file, save it, and you're done. IMHO this would be the preferred method - no camera/recorder connection or Lockits required, no software like Plural Eyes required either, and no worry about whether your editing software can read an LTC track or not.
 
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Steve House said:
Linear timecode (which is what we're talking about here) is actually encoded as a pulse-modulated audio signal, similar in principle to that of an old-fashioned acoustic modem. Any timecode device with a "TC Out" terminal sends it in that format and it can be recorded to an audio track by any conventional recorder like any other audio signal. Whether your editing software can decode and use that audio track depends on the software you have.

In video, one of the classic workflows is audio slaves to video. So your camera generates the timecode and records it as VITC in with the video. At the same time, it outputs the same code as LTC audio and sends it over to the audio recorder. In the audio recorder the LTC is recorded on one channel of a stereo track while the audio (mono) is recorded on the other. In post you drop the video into the timeline so that the embedded VITC aligns to the project timeline. Then you drop in the audio file and if the NLE can read the timecode channel, it positions it in the project where the recorded LTC matches the code on the project timeline. Since the mono actual audio channel is locked to the LTC channel this also positions the desired audio in sync with the video. Lock the audio and video tracks together, delete the LTC track, and you're done syncing. Obviously this doesn't work with a DSLR because it doesn't generate and output timecode.

The HDSLR situation would be a variation on this workflow. The recorder would generate timecode and send it to the camera's mic input to be recorded in lieu of actual audio. Over in the recorder, the timecode coinciding with the first audio sample is stamped into the audio file header. As the shot proceeds, the audio recorder's timecode is continuously sent to the camera and recorded there as the audio track alongside the video. In post, you'd drop the combined video/TC audio file into the project, aligning the embedded audio TC to the project's timeline, again assuming your editing software can decode the TC in the audio track. Drop in the audio file from the recorder and the NLE positions it on the project timeline according to the timecode timestamp embedded in the file header. Mute the TC track associated with the video track, lock the audio track from the external recorder to the video, and you're synced.

Another possible timecode workflow with an HDSLR would be to use a classic filmstyle smart-slate. The audio recorder serves as the timecode master. A smart-slate that displays TC is jammed with it so the timecode clock in the audio recorder and running on the slate are identical. The slate is photographed as you start to roll. The audio recorder's timecode goes into the file header timestamp. To sync in post you drop the video track into the editor and adjust the project timeline's timecode so it matches the code visible frame by frame on the photographed image on the slate. Then you drop in the audio file, letting the software position in on the timeline, aligning the embedded timestamp in the file header with the project timeline code. Voila! you're in sync. Replace the scratch audio originally recorded in the camera with the audio from the externally recorded file, save it, and you're done. IMHO this would be the preferred method - no camera/recorder connection or Lockits required, no software like Plural Eyes required either, and no worry about whether your editing software can read an LTC track or not.
Click to expand...
First off, thank you VERY much for taking the time to type that all out for me! It was what I was assuming, but to have it all spelled out and confirmed was very helpful.

Now, that being said, right off the bat I do love the idea of a smart slate not only for the ease of post syncing that it would create but also because it would mean no cable running to the camera from the recorder (I can just see that getting hit and bringing a camera tripod setup to the floor). However those smart slates all seem to be quite expensive and not something I could afford at the moment with so much going out already on other stuff.

So, the other option of embedding the timecode signal directly onto the camera audio track sound like a less expensive and thus better option for me for the time being. I was thinking however that it might be advantageous (in a redundancy sense) to utilize the fact that the mic in on these DSLR cameras is stereo and therefore offers two tracks that can be recorded for reference. So what do you think about using a 1/8" stereo to two mono splitter and have say the left channel be the timecode data from the 702T and the right channel be an on board hotshoe mount mic like say the Rode VideoMic Pro and use that as a backup just in case syncing via timecode doesnt work for whatever reason? Would that be possible or at all beneficial?
 
Alex H... Steve's HDSLR timecode workflow explanation seems worthy of being included in the Audio 101 sticky. Well written & very informative. Kudos to Steve.

Does anyone know if Final Cut Studio 7 or FCPX have the ability to decode LTC like Avid (Media Composer?) does?

To the OP: Personally, I would only consider buying the 702T. Timecode may not be something you use now, but the deeper you get into production sound down the road, you'll likely be glad you have it. The fact that I don't own a recorder with timecode has been a stumbling block for me a few times. I agree that smart slates are prohibitively expensive, but they're relatively inexpensive to rent. One reason I haven't gone out and bought a 702T is that I'm even more interested in the base model of the Zaxcom Nomad. The other reason I haven't thrown down such a huge wad of money like that is that most productions are uber-low-balling sound people, and expect you to show up with $30,000 worth of gear and be paid a total of $200 for a 19 hour day. This is an entirely different subject, and not one I wish to discuss in this thread.
 
Sam Mallery said:
...One reason I haven't gone out and bought a 702T is that I'm even more interested in the base model of the Zaxcom Nomad. The other reason I haven't thrown down such a huge wad of money like that is that most productions are uber-low-balling sound people, and expect you to show up with $30,000 worth of gear and be paid a total of $200 for a 19 hour day. This is an entirely different subject, and not one I wish to discuss in this thread.
Click to expand...
That's the reason I've held out myself Sam. The Nomad looks like it would be a great ENG/bag recorder and easily able to switch over to a solid cart-based recorder with either a Mix-8 in front or a nice analog mixer. Have used the 702t many times and love how light it is (compared to the 744t). Have considered jumping on a used one for some time now, but more and more people want ISO's so for those gigs where you play the bit-bucket, having extra tracks might make or break your ability to get that gig which could help pay for the unit.
 
Excellent write up by Steve.

With the new Canon EOS 1D X camera having time code, I am sure slowly other DSLR cameras will also start getting timecode. It would be worth having the 702T in your bag.
 
A no brainer to me. Double system sound with a 702T and smart slate. It's one thing to record audio to the DSLR, it's another thing for that to be the primary audio. Also, a 2-track recorder is still fine for most narrative production (still the standard).
 
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