View Full Version : Edirol R4 Pro & Red
05-07-2008, 03:46 PM
I have been testing an Edirol R4 Pro 4 channel audio disk recorder today with my Red.
Syncing timecode was easy. Red Jam synced to the Edirol just fine using the Sound Device Lemo-5 to BNC cable from B&H.
It was easy to name the clips in Edirol to match the file names on the Red media. Or very close anyway.
A012_001.wav - A012_C001_080507
One problem I am having is the Edirol does a weird 24 timecode. Instead of 0-23 it writes 0-60 and skips numbers so it ends up with 24 frames.
This was a problem at first when I would try to sync 14:12:23:20 in the wav file to 14:12:23:20 in the Red file. My audio would be off. If I sync both to 14:12:23:00 they match perfectly. As long as I sync both to 00 frames the audio seems to be in perfect sync.
Now I am going to do some long record tests and see if there is any drift.
Is there anything else someone would like me to test?
05-07-2008, 08:30 PM
There appears to be drift in the TC between the Red and R4 Pro. A few frames per hour. I am doing some more testing to make sure I didn't do anything wrong.
So my questions now becomes, if the timecode is drifting, is there any reason to use it? If not then maybe I should just look at getting R4 or R44.
The filenames match and I can use a clapper to sync, so how important is timecode?
05-07-2008, 09:15 PM
How does it handle other RED frame rates like 23.98, 29.97 etc?
05-07-2008, 10:57 PM
I haven't had a chance to check other framerates. Only 23.976.
The R4 Pro records the wrong timecode a lot. I tell it to be 23.976, but sometimes the files are 59.94.
After more testing it seems like the R4 Pro audio drifts .75 of a frame every 10 minutes.
The timecode is in sync between the .wav and the .mov, but the sound is out.
I was recording the audio at 48k/16bit and the FCP timeline was 48k/32bit. Could that conversion somehow cause the drift?
I need to do more testing.
05-08-2008, 08:28 AM
interesting...I just purchased one of these but have not had time to test it with the RED.
The testing with the SD 744t also showed some drift. I guess if you can figure out the uniformity of the drift, it is a simple matter to synch. But a pain nonetheless and not what we paid extra money for, as you say.
Looking forward to more of your testing results.
05-14-2008, 08:31 PM
I think you may be right about the different resolutions having an effect but only a test will tell for sure.
If you were to use the R4 Pro as an outboard mixer, how do you handle the fact that it does not have +4 balanced outputs?
BTW, Are you in Texas or Hawaii? I'm on the Big Island.
05-14-2008, 11:07 PM
I have been in Texas for a little over a year now. My wife is from Kailua (Oahu) and I lived on Oahu for about 15 years. We really miss home, but Texas is so much more affordable. I come back to Hawaii as much as I can.
I was never planning to use the R4 Pro as an outboard mixer. Just send reference audio to the camera. The R4 has four RCAs out, but I found it easier to just use the headphone out with a spliter to send a reference mixdown to the camera.
The audio coming thru the R4 to the camera was 2 frames behind picture. This was constant and did not drift. Just that much delay in getting thru the R4.
I had to take the R4 Pro back to the rental house before I got to do any more testing.
A couple other tests I would have liked to do is:
1. leave the TC cable connected and see if the audio still drifts.
2. try using a timecode generator to control the TC in the R4. Sync the Red to the TC generator, then connect the TC generator to the R4 Pro and leave it connected.
05-15-2008, 02:23 PM
I'll be getting my RED in a few weeks so maybe I can do some of those tests.
Thanks for sharing your info. It will save me some time. Hope to see you back in the islands some day.