These instructions use timecode to sync sound recorded on a 744t to video recorded on a scarlet.
My exact config:
RED Sync to bnc cable (the epic/scarlet one ... has 3 bnc's, if you use red one, you need the 2 bnc cable).
bnc2bnc connector sound device cable "xl-lb2 lemo to BNC i/O cable" ( most film productions do it fancier then this).
Sound Device 744t.
Reset the sound device 744t to "film" (this put the sound device into a default state, this is almost the same as default but put's mic 1&2 into phantom mode, it only needs to occur once when you get the 744t).On the scarlet, set the timecode to external.(I also am always in QHD mode, 24 fps, 1/24th time ... with the project set a 24 fps, i haven't tested the other modes).Turn off both the 744t and scarlet/epic (i'm not sure this is necessary ... but i'm paranoid on connecting cables with power on). Connect your mic's (i use a Seinheiser 416, by default you get 4 lines recording btw). Connect the sound device cable "xl-lb2 lemo to BNC i/O cable) to the 744t time code lemo connector. Connect a bnc-2-bnc connecter to the sound device cable bnc. Connect a 3 bnc to sync cable (from red, it's a 2 bnc for red one) to the scarlet/epic. Connect the Yellow bnc of the scarlet's sync cable to the bnc-2-bnc connector.
You should now have your 744t connected to your scarlet. Hook up your mics (with film mode, mic 1& 2 are default phantom btw). Turn on you sound device 744t. Turn on your scarlet/epic. You should notice that the times are exactly the same on the scarlet and the sound device(default modes auto send the timecode). I always hit the "menu" and the "hdd" button .... then do the menu select on "jam zero". You can now disconnect the yellow BNC connector (atleast I have noticed no drift in a hour), this allows free movement of the camera.
Hit Record on the 744t and Hit record on the scarlet. Clap your hands ( I was getting some fancy timecode clapper, this ended up working perty good for me and a lot cheaper). Turn power off on the scarlet, then 744t. Take out the red ssd, and the sandisk from the 744t (it also records to internal disk ... so u can also connect the 774t to your computer if u want to copy that way). Copy the RED R3d files to some folder on your computer. Copy the wav files from the sound device to some folder on your computer.
Final Steps to Verify using adobe premiere, so Open Adobe Premiere (create a project.drag the r3d and wave file into the adobe project).
---------------------- next few steps are "optional" ... not sure exactly why some of this happens ---------------
To shift the audio by one frame (if your having problems with audio offset this is a possible tweak): right click wav file in project panel, select modify -> timecode change frame from 00 to 01, should have "set at beginning" click "ok".
If your .wav files are not showing the time code in "media start"column ... i.e. the media start time should not be a string of zero's then do this:on the main menu click Edit->preferences->media .... then click on the "media cache database" "clean"also there are three fields there, i'm finding good look having it set at 24 fps, use media source and start at 0 (my manual claps seem to have less frame issues). This btw is some weird bug, will be fixed soon i hope(happens to me every every now and then).
Back to "normal" things ..... Select the video clip you wish to merge audio clips to. Note that you can only have one video clip in any merged clip. Control-click audio and video clip. right click for menu to and select "Merge Clips" and select timecode. The Merge Clips dialog launches. Choose - Based on matching timecode.
A new file should be in your project area in premiere, drag that to the time line ... and the sound will be synced. In the timeline, find where your hands clap, zoom into the exact frame, you should be able to see your hands clap at the same exact frame you hear the clap.